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177-737: The plain is the surface of an in-filled system of ancient canyons (the "Apennine Foredeep") extending from the Apennines in the south to the Alps in the north, including the northern Adriatic. In addition to the Po and its affluents, the contemporary surface may be considered to include the Savio , Lamone and Reno to the south, and the Adige , Brenta , Piave and Tagliamento of the Venetian Plain to

354-555: A Berriasian–Barremian warm-dry phase, an Aptian–Santonian warm-wet phase, and a Campanian–Maastrichtian cool-dry phase. As in the Cenozoic, the 400,000 year eccentricity cycle was the dominant orbital cycle governing carbon flux between different reservoirs and influencing global climate. The location of the Intertropical Convergence Zone (ITCZ) was roughly the same as in the present. The cooling trend of

531-759: A big contributor to pollution. It delivers more than 40 percent of Italy's milk production, for example, while over half of the Italian pig production is located in the Po Valley. According to research published in The Lancet Planetary Health in January 2021, which estimates the death rate associated with fine particulate matter (PM 2.5 ) and nitrogen dioxide (NO 2 ) pollution in 1000 European cities, Brescia and Bergamo in Lombardy have

708-548: A derivation with which they all agree. Wilhelm Deecke said: "[…] its etymology is doubtful but some derive it from the Ligurian-Celtish Pen or Ben , which means mountain peak." A large number of place names seem to reflect pen : Penarrig, Penbrynn, Pencoid, Penmon, Pentir, etc. or ben : Beanach, Benmore, Benabuird, Benan, Bencruachan, etc. In one derivation Pen/Ben is cognate with Old Irish cenn , 'head', but an original *kwen- would be required, which

885-477: A geologic feature called the fontanili ("spring") line or zone, a band of springs around the Val Po, heaviest on the north, on the lowermost slopes of the anticline. It varies from a few kilometres to as much as 50 km (30 miles) wide. The fontanili line is the outcrop, or intersection, of the anticline's water table with the surface at the edge of the bassa . The rock above the line is porous. Surface water in

1062-615: A geologic signature associated with the mass extinction that lies between the Mesozoic and Cenozoic Eras . The Cretaceous as a separate period was first defined by Belgian geologist Jean d'Omalius d'Halloy in 1822 as the Terrain Crétacé , using strata in the Paris Basin and named for the extensive beds of chalk ( calcium carbonate deposited by the shells of marine invertebrates , principally coccoliths ), found in

1239-566: A lower sea level that allowed big mammals and humans to migrate from Africa and the Middle East to central and western Europe through an empty and open Po valley, avoiding the barrier of the Alps, reaching the Loire Valley, and Iberian Peninsula, and then, when glaciation retreated, the rest of continental Europe. Urban development began in the Po Valley much later than in southern Italy or Greece. The first known ancient inhabitants of

1416-716: A lower, very fertile, and well-irrigated section, known in Lombardy and western Emilia as la Bassa , "the low (plain)". The upper areas of the Po valley take local names which reflect in their meanings their being modestly suited for farming. So we have the Piedmontese vaude and baragge , the Lombard brughiere and Groane , or, exiting from the Po valley proper, the Friulian magredi , areas remote from easily reachable water tables and covered with dense woods or dry soils. This specific meaning for "lower plain" derive from

1593-477: A more significant constituent in the average diet and in the agrarian regime compared to the centuries before, leading populations to reconfigure the medieval natural landscape for agricultural purposes. In creating new land for cultivation and settlement, the European communities triggered a massive landscape transformation through woodland clearance, arable intensification, the development of irrigation systems and

1770-544: A picked corps) on special police duty with a detachment of twenty men from the Ravenna fleet. Snow lies on the highest peaks of the Apennines for almost the whole year. The range produces no minerals, but there are a considerable number of good mineral springs , some of which are thermal (such as Bagni di Lucca , Montecatini , Monsummano , Porretta, Telese), while others are cool (such as Nocera, Sangemini , Cinciano),

1947-715: A series of tunnels have been constructed to conduct "the Bologna-Florence rail line", which is neither a single line nor a single tunnel. The Porrettana Line went into service in 1864, the Direttissima in 1934 and the High Speed in 1996. A few dozen tunnels support the three of them, the longest on the High-Speed Line being the Voglia Tunnel at 16.757 km (10.412 mi). The longest is on

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2124-465: A singular with plural meaning; Italian : Appennini [appenˈniːni] ) are a mountain range consisting of parallel smaller chains extending c.  1,200 km (750 mi) the length of peninsular Italy . In the northwest they join the Ligurian Alps at Altare . In the southwest they end at Reggio di Calabria , the coastal city at the tip of the peninsula. Since 2000

2301-701: A stone marks the top of the pass. In the vicinity are fragments of the old road and three ruins of former fortifications. At Carcare , the main roads connect with the upper Bormida valley (Bormida di Mallare) before turning west. The Scrivia , the Trebbia and the Taro , tributaries of the Po River , drain the northeast slopes. The range contains dozens of peaks. Toward the southern end the Aveto Natural Regional Park includes Monte Penna . Nearby

2478-674: A straight shell, flourished in the seas along with reef-building rudist clams. Inoceramids were also particularly notable among Cretaceous bivalves, and they have been used to identify major biotic turnovers such as at the Turonian-Coniacian boundary. Predatory gastropods with drilling habits were widespread. Globotruncanid foraminifera and echinoderms such as sea urchins and starfish (sea stars) thrived. Ostracods were abundant in Cretaceous marine settings; ostracod species characterised by high male sexual investment had

2655-565: A year of their life expectancy. The main reasons for the high amount of air pollution over the Po valley are strictly connected to livestock and factories. The so-called "NPK fertilizers", made of nitrogen, phosphorus and potassium, along with manure emissions from intensive breeding and high levels of nitrogen dioxide released by diesel and petrol engines are all accountable for this disastrous air condition in Northern Italy. The region of Lombardy produces also vast amounts of animal waste,

2832-564: A ~0.6 °C increase in temperature. The latter warming interval, occurring at the very end of the Cretaceous, was triggered by the activity of the Deccan Traps. The LKEPCI lasted into the Late Palaeocene , when it gave way to another supergreenhouse interval. The production of large quantities of magma, variously attributed to mantle plumes or to extensional tectonics , further pushed sea levels up, so that large areas of

3009-526: Is an almost continuous megalopolis stretching from Turin to Trieste . The bassa Padana was settled and farmed earliest, in Etruscan and Roman times. After the collapse of the Roman Empire (5th century AD), lack of maintenance of the irrigation systems associated with a cooling climate phase (i.e. the so-called Migration Period or The Dark Age Cold Period ) led to the progressive waterlogging of

3186-606: Is at about 3,200 m (10,500 ft), leaving the Apennines below it, except for the one remaining glacier. Snow may fall from October to May. Rainfall increases with latitude. The range's climates, depending on elevation and latitude, are the Oceanic climate and Mediterranean climate . The mammal fauna is mainly composed of Italian wolves (endemic), Corsican hare , badgers , weasels , foxes , marmots , Etruscan shrew , Crested porcupine , European snow vole and Apennine shrews (endemic), Marsican brown bears (endemic),

3363-571: Is claimed to be likely to be lost due to soaring sea level in the next centuries. Where the land surface now dips below sea level the river must run at a relative elevation between dikes. The Malossa gas condensate field was discovered in 1973 and produces at depths of 6 km (4 miles) from the Upper Triassic Dolomia Principale dolomite and the Lower Jurassic Zandobbio dolomite, capped by

3540-629: Is deep and separates the Apennines on the left bank from a lesser range, the Tuscan Anti-Apennines (Sub-Apennines) on its right. The Apennine System forms an irregular arc with centers of curvature located in the Tyrrhenian Sea. The northern and southern segments comprise parallel chains that can be viewed as single overall mountain ridges, such as the Ligurian Mountains. The center, being thicker and more complex,

3717-455: Is for hydro-electric power, irrigation, and industrial transport. The cost of purifying it for human consumption makes that process less feasible. The fresh drinking water comes from hundreds of thousands of wells concentrated especially in the fontanili zone. The major settlements, therefore, are also in that zone, which has become the centre of economic development and industry in Italy, and now

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3894-619: Is found in England, northern France, the low countries , northern Germany , Denmark and in the subsurface of the southern part of the North Sea . Chalk is not easily consolidated and the Chalk Group still consists of loose sediments in many places. The group also has other limestones and arenites . Among the fossils it contains are sea urchins , belemnites , ammonites and sea reptiles such as Mosasaurus . In southern Europe,

4071-663: Is geologically divided into an inner and an outer arc with regard to the centers of curvature. The geologic definition, however, is not the same as the geographic. Based on rock type and orogenic incidents, the northern segment of the arc is divided into the Outer Northern Apennines (ONA) and the Inner Northern Apennines (INA). The Central Apennines are divided into the Umbrian–Marchean ( Appennino umbro-marchigiano ) or Roman Apennines in

4248-470: Is mainly grasslands of the Montane grasslands and shrublands biome; with Temperate broadleaf and mixed forests, and Mediterranean forests, woodlands, and scrub below it. The tree line in the Apennines can be found in the range 1,600 m (5,200 ft) to 2,000 m (6,600 ft). About 5% of the map area covered by the Apennines is at or above the tree line—or in the treeline ecotone. The snow line

4425-544: Is part of the Monti Sibillini , incorporated into Parco Nazionale dei Monti Sibillini . Further north is the parco naturale regionale della Gola della Rossa e di Frasassi  [ it ] , in which are the Gola della Rossa ("Red Gorge") and Frasassi Caves . Still further north is Parco Sasso Simone e Simoncello. The Italian Park Service calls it the "green heart" of Italy. The region is heavily forested , such as

4602-598: Is produced by the flow of the Po. The river is extensively used for irrigation for the region's agriculture. Po valley is considered the worst area in Europe for air quality. In March 2019, the European Space Agency (ESA) published images of nitrogen dioxide concentrations taken from the Sentinel-5P satellite. These images show a big red area, made of nitrogen dioxide and fine particles, situated above

4779-566: Is the Bocca Serriola Pass in northern Umbria , which links Fano and Città di Castello . The Tiber River at Rome flows from Monte Fumaiolo in the Tuscan-Romagnol Apennine from northeast to southwest, projecting into the Tyrrhenian Sea at right angles to the shore. The upper Tiber, however, flows from northwest to southeast, gradually turning through one right angle clockwise. The northern Tiber Valley

4956-779: Is the Italian sparrow . The reasons for this choice are related to the fact that the Italian wolf, which inhabits the Apennine Mountains and the Western Alps , features prominently in Latin and Italian cultures, such as in the legend of the founding of Rome . In Italy the transhumance took place mainly starting from the Abruzzi Apennines, moving both towards the Tuscan and Lazio Maremma and above all towards

5133-421: Is the highest point of Ligurian Apennines, Monte Maggiorasca at 1,800 m (5,900 ft). The main and only feasible overland route connecting the coastal plain of Liguria to the north Italian plain runs through Bocchetta di Altare. It has always been of strategic importance. Defenders of north Italy have had to control it since ancient times, as the various fortifications placed there testify. Trenitalia ,

5310-479: Is typologically not found in languages that feature labio-velars . Windisch and Brugmann reconstructed Indo-European *kwi- , deriving also the Greek Pindus Mountains from the same root, but *kwen- < *kwi- is not explained by any rule. By some, English pin , as well as pen and Latin pinna or penna , 'feather' (in the sense of the horn of the quill), have been connected to

5487-464: The Alpine system . Prior to the explosion of data on the topic from about the year 2000, many authors took the approach that the Apennines had the same origin as the Alps. Even today, some authors use the term Alpine-Apennine system. They are not, however, the same system and did not have the same origin. The Alps were millions of years old before the Apennines rose from the sea. The northward movement of

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5664-628: The Aterno from the north-west and the Gizio from the south-east, is more important; and so is the Sangro . The central Apennines are crossed by the railway from Rome to Pescara via Avezzano and Sulmona: the railway from Orte to Terni (and thence to Foligno ) follows the Nera valley; while from Terni a line ascends to the plain of Rieti, and thence crosses the central chain to Aquila, whence it follows

5841-728: The Eurasian eagle-owl There are also numerous amphibians such as the Apennine yellow-bellied toad (endemic), the Italian cave salamander (endemic), the Italian newt (endemic), the Italian stream frog (endemic) and the Spectacled salamander (endemic), the Italian tree frog (endemic), the Agile frog , the Italian edible frog (endemic), the Common toad , the Balearic green toad ,

6018-684: The European fallow deer , the European mouflon and the Pyrenean chamois . There are also numerous birds such as the golden eagle , the Bonelli's eagle , the Eurasian goshawk , the hoopoe , the hawk , the European roller , the White-backed woodpecker , the European green woodpecker , the Alpine chough , the Egyptian vulture , the European nightjar , the Italian sparrow (endemic) and

6195-554: The Guelph-Ghibelline reciprocate bloodbath of the 13th and 14th centuries. The Signorie came from spent out Communal institutions. With Venice 's expansion on the eastern mainland in the first half of the 15th century and Milan 's supremacy in the center and west the region (not significantly diminished by the Black Death of 1348) reached unprecedented peaks of prosperity. Vast areas were irrigated and cultivated with

6372-643: The Ligurian Sea in the Gulf of Genoa , from about Savona below the upper Bormida River valley to about La Spezia ( La Cisa pass ) below the upper Magra River valley. The range follows the Gulf of Genoa separating it from the upper Po Valley . The northwestern border follows the line of the Bormida River to Acqui Terme . There the river continues northeast to Alessandria in the Po Valley , but

6549-703: The Majella Massif. Among them are two national parks: Gran Sasso e Monti della Laga National Park and Majella National Park ; and the Regional Park of the Monti Simbruini. Gran Sasso contains Corno Grande , the highest peak of the Apennines (2912 m). Other features between the western and central ranges are the plain of Rieti , the valley of the Salto, and the Lago Fucino ; while between

6726-713: The Mancos Shale of western North America. These shales are an important source rock for oil and gas , for example in the subsurface of the North Sea. In northwestern Europe, chalk deposits from the Upper Cretaceous are characteristic for the Chalk Group , which forms the white cliffs of Dover on the south coast of England and similar cliffs on the French Normandian coast. The group

6903-462: The North American Cordillera , as the Nevadan orogeny was followed by the Sevier and Laramide orogenies . Gondwana had begun to break up during the Jurassic Period, but its fragmentation accelerated during the Cretaceous and was largely complete by the end of the period. South America , Antarctica , and Australia rifted away from Africa (though India and Madagascar remained attached to each other until around 80 million years ago); thus,

7080-399: The Northern spectacled salamander (endemic), the Fire salamander , the Smooth newt , the Alpine newt , and the Italian crested newt . The reptile fauna is mainly composed of suc as the Italian Aesculapian snake (endemic), the Dice snake , the Green whip snake , the Aesculapian snake , the Smooth snake , the Vipera ursinii , the Vipera aspis , the Italian wall lizard (endemic),

7257-421: The Po Valley in northern Italy. Compressional forces have been acting from north to south in the Alps and from south to north in the Apennines, but instead of being squeezed into mountains the valley has been subsiding at 1 to 4 mm (0.16 in) per year since about 25 mya , before the Apennines existed. It is now known to be not an erosional feature, but is a filled portion of the Adriatic Trench, called

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7434-407: The Podarcis muralis , the European green lizard . Notable Apennine freshwater fishes are the Brook lamprey (endemic), Lombardy lamprey , Italian bleak (endemic), Horse barbel (endemic), Eurasian carp , Scardola scardafa (endemic), European perch , Chubius Chub , Tench and Northern pike . The Italian wolf is the national animal of Italy, while the national bird of the country

7611-403: The Pollino National Park , the Vesuvius National Park , the Cilento, Vallo di Diano and Alburni National Park , the Appennino Lucano - Val d'Agri - Lagonegrese National Park , the Sila National Park , the Aspromonte National Park . Important rivers originate from the Apennines are the Panaro , the Secchia , the Reno , the Marecchia , the Rubicon , the Metauro , the Arno , the Tiber ,

7788-425: The Savio , the Nera , the Velino , the Tronto , the Aterno-Pescara , the Aniene , the Liri , the Sangro and the Volturno . Among the lakes of glacial origin of the Alpine type is Lago di Pilato . The Apennines were created in the Apennine orogeny beginning in the early Neogene (about 20 mya , the middle Miocene ) and continuing today. Geographically they are partially (or appear to be) continuous with

7965-441: The Selli Event . Early Aptian tropical sea surface temperatures (SSTs) were 27–32 °C, based on TEX 86 measurements from the equatorial Pacific. During the Aptian, Milankovitch cycles governed the occurrence of anoxic events by modulating the intensity of the hydrological cycle and terrestrial runoff. The early Aptian was also notable for its millennial scale hyperarid events in the mid-latitudes of Asia. The BAWI itself

8142-399: The Tavoliere delle Puglie . The Apennines are to some extent covered with forests, though these were probably more extensive in classical times ( Pliny mentions especially pine , oak and beech woods, Hist. Nat . xvi. 177); they have indeed been greatly reduced in comparatively modern times by indiscriminate timber-felling, and though serious attempts at reforestation have been made by

8319-538: The Turonian Age, based on isotopic evidence. However, this has subsequently been suggested to be the result of inconsistent isotopic proxies, with evidence of polar rainforests during this time interval at 82° S. Rafting by ice of stones into marine environments occurred during much of the Cretaceous, but evidence of deposition directly from glaciers is limited to the Early Cretaceous of the Eromanga Basin in southern Australia . Flowering plants (angiosperms) make up around 90% of living plant species today. Prior to

8496-413: The Venetian domain was invaded, forcing Venice into neutrality as an independent power. In the end, Spain prevailed with Charles V 's victory over Francis I of France at the Battle of Pavia in 1525. The Spanish domination was oppressive, adding its burden to the Counterreformation imposed by the archbishopric of Milan ; Protestantism was prevented from making inroads in the area. Burning at

8673-430: The intermittent streams of the mountains tends to disappear below ground only to spring out again in the spring zone . The spring zone is often called "the middle valley." Surface runoff water (the Po and its affluents) is not of much value to the valley's dense population for drinking and other immediate uses, being unreliable, often destructive, and heavily polluted by sewage and fertilizers. Its main anthropic value

8850-414: The kingdom of Italy , always with its capital in Pavia. The affirmation of large landownership from the eighth/ninth centuries accelerated the process of land reclamation and intensified land use, transforming the landscape of the Po Valley. After the chaotic feudal dissolution of the empire and much fighting among pretenders to the imperial crown, Otto I of Saxony set the stage for the following phase of

9027-409: The orogeny . These extend in a northwest–southeast direction from the River Tronto to the River Sangro , which drain into the Adriatic . The coastal hills of the east extend between San Benedetto del Tronto in the north and Torino di Sangro in the south. The eastern chain consists mainly of the southern part of the Monti Sibillini , the Monti della Laga , the Gran Sasso d'Italia Massif and

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9204-417: The tuatara ) disappeared from North America and Europe after the Early Cretaceous , and were absent from North Africa and northern South America by the early Late Cretaceous . The cause of the decline of Rhynchocephalia remains unclear, but has often been suggested to be due to competition with advanced lizards and mammals. They appear to have remained diverse in high-latitude southern South America during

9381-401: The 20th century) came the Germanic Lombards , a warrior people who gave their name to almost the whole of the Po valley: Lombardy . In the Middle Ages the term was used to indicate all of northern Italy. The Lombards divided their domain in duchies , often contending for the throne; Turin and Friuli, in the extreme west and east end respectively, seem to have been the most powerful, whereas

9558-441: The Adriatic foredeep after its function as a subduction zone was discovered. Cretaceous The Cretaceous ( IPA : / k r ɪ ˈ t eɪ ʃ ə s / krih- TAY -shəss ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era , as well as the longest. At around 79   million years, it is the ninth and longest geological period of

9735-421: The African Plate and its collision with the European Plate then caused the Alpine Orogeny , beginning in the late Mesozoic. The band of mountains created extends from Spain to Turkey in a roughly east–west direction and includes the Alps. The Apennines are much younger, extend from northwest to southeast, and are not a displacement of the Alpine chain. The key evidence of the difference is the geologic behavior of

9912-678: The Albian regularly expanded northward in tandem with expansions of subtropical high pressure belts. The Cedar Mountain Formation's Soap Wash flora indicates a mean annual temperature of between 19 and 26 °C in Utah at the Albian-Cenomanian boundary. Tropical SSTs during the Cenomanian-Turonian Thermal Maximum were at least 30 °C, though one study estimated them as high as between 33 and 42 °C. An intermediate estimate of ~33-34 °C has also been given. Meanwhile, deep ocean temperatures were as much as 15 to 20 °C (27 to 36 °F) warmer than today's; one study estimated that deep ocean temperatures were between 12 and 20 °C during

10089-483: The Alps and Apennines as far as the sources of the tributaries of the Po but excludes Veneto and that portion of Emilia-Romagna south of the lower Po; that is, it includes the region drained by the Po but only the Po and its tributaries. The altitude of the valley through which the Po flows, exclusive of its tributaries, varies from approximately 4 m (15 feet) below sea level in the Polesine subregion (the delta around Ferrara ) to about 2,100 m (6,900 feet) at

10266-447: The Alps. The shoreline of the Adriatic depends on a balance between the sedimentation rate and isostatic factors. Until about 1950, the Po delta was prograding into the Adriatic. After that time due to human alteration of geologic factors, such as the sedimentation rate, the delta has been degrading and the coastline subsiding, resulting in ongoing contemporaneous crises in the city of Venice , where much irreplaceable art and architecture

10443-538: The Apennine range, and so are Cilento hills on the west. On the converse the promontory of Mount Gargano , on the east, is completely isolated, and so are the Campanian volcanic arc near Naples . The district is traversed from north-west to south-east by the railway from Sulmona to Benevento and on to Avellino , and from south-west to northeast by the railways from Caianello via Isernia to Campobasso and Termoli, from Caserta to Benevento and Foggia, and from Nocera Inferiore and Avellino to Rocchetta Sant'Antonio,

10620-435: The Calabrian southern Apennine Mountains extend along the northern coast of Sicily (the Sicilian Apennines, Italian Appennino siculo )— Pizzo Carbonara (6,493 feet (1,979 m)) being the highest peak. The number of vascular plant species in the Apennines has been estimated at 5,599. Of these, 728 (23.6%) are in the treeline ecotone . Hemicryptophytes predominate in the entire Apennine chain. The tree line ecotone

10797-427: The Cenomanian between the Albian and Turonian. The Cretaceous is divided into Early and Late Cretaceous epochs , or Lower and Upper Cretaceous series . In older literature, the Cretaceous is sometimes divided into three series: Neocomian (lower/early), Gallic (middle) and Senonian (upper/late). A subdivision into 12 stages , all originating from European stratigraphy, is now used worldwide. In many parts of

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10974-510: The Cenozoic Era   —   the ichthyosaurs , last remaining temnospondyls ( Koolasuchus ), and nonmammalian cynodonts ( Tritylodontidae )   —   were already extinct millions of years before the event occurred. Coccolithophorids and molluscs , including ammonites , rudists , freshwater snails , and mussels , as well as organisms whose food chain included these shell builders, became extinct or suffered heavy losses. For example, ammonites are thought to have been

11151-407: The Coniacian through the Maastrichtian. During the Cretaceous, the late- Paleozoic -to-early-Mesozoic supercontinent of Pangaea completed its tectonic breakup into the present-day continents , although their positions were substantially different at the time. As the Atlantic Ocean widened, the convergent-margin mountain building ( orogenies ) that had begun during the Jurassic continued in

11328-401: The Cretaceous is sharply defined, being placed at an iridium -rich layer found worldwide that is believed to be associated with the Chicxulub impact crater , with its boundaries circumscribing parts of the Yucatán Peninsula and extending into the Gulf of Mexico . This layer has been dated at 66.043 Mya. At the end of the Cretaceous, the impact of a large body with the Earth may have been

11505-402: The Cretaceous is usually a marine system consisting of competent limestone beds or incompetent marls . Because the Alpine mountain chains did not yet exist in the Cretaceous, these deposits formed on the southern edge of the European continental shelf , at the margin of the Tethys Ocean . During the Cretaceous, the present North American continent was isolated from the other continents. In

11682-425: The Cretaceous seas. Stagnation of deep sea currents in middle Cretaceous times caused anoxic conditions in the sea water leaving the deposited organic matter undecomposed. Half of the world's petroleum reserves were laid down at this time in the anoxic conditions of what would become the Persian Gulf and the Gulf of Mexico. In many places around the world, dark anoxic shales were formed during this interval, such as

11859-434: The Direttissima, the Great Apennine Tunnel, which at 18.5 kilometres (11.5 miles) is the longest entirely within Italy, although the Simplon Tunnel , which connects Italy and Switzerland, is longer. Automobile traffic is carried by the Autostrada del Sole, Route A1, which goes through numerous shorter tunnels, bypassing an old road, originally Roman, through Futa Pass. In December 2015, a new Route A1 called Variante di Valico

12036-429: The Environment Ministry of Italy, following the recommendations of the Apennines Park of Europe Project, has defined the Apennines System to include the mountains of north Sicily , a total distance of 1,500 kilometres (930 mi) . The system forms an arc enclosing the east of the Ligurian and Tyrrhenian seas. The Apennines conserve some intact ecosystems that have survived human intervention. In these are some of

12213-434: The Greeks and Sicilians with timber for shipbuilding. The railway from South Eufemia to Catanzaro and Catanzaro Marina crosses the isthmus, and an ancient road may have run from Squillace to Monteleone. The second group extends to the south end of the Italian Peninsula , culminating in the Aspromonte (1,960 metres (6,420 ft)) to the east of Reggio di Calabria . In both groups the rivers are quite unimportant. Finally,

12390-420: The Jurassic, the North Atlantic already opened, leaving a proto-ocean between Europe and North America. From north to south across the continent, the Western Interior Seaway started forming. This inland sea separated the elevated areas of Laramidia in the west and Appalachia in the east. Three dinosaur clades found in Laramidia (troodontids, therizinosaurids and oviraptorosaurs) are absent from Appalachia from

12567-415: The LKEPCI. During this period of relatively cool temperatures, the ITCZ became narrower, while the strength of both summer and winter monsoons in East Asia was directly correlated to atmospheric CO 2 concentrations. Laramidia likewise had a seasonal, monsoonal climate. The Maastrichtian was a time of chaotic, highly variable climate. Two upticks in global temperatures are known to have occurred during

12744-638: The Late Bronze Age as it is defined in Greece and the Aegean. The people of the Apennine culture were alpine cattle herdsmen grazing their animals over the meadows and groves of mountainous central Italy. They lived in small hamlets located in defensible places. On the move between summer pastures they built temporary camps or lived in caves and rock shelters. Their range was not necessarily confined to

12921-599: The Late Cretaceous, where lizards remained rare, with their remains outnumbering terrestrial lizards 200:1. Choristoderes , a group of freshwater aquatic reptiles that first appeared during the preceding Jurassic, underwent a major evolutionary radiation in Asia during the Early Cretaceous, which represents the high point of choristoderan diversity, including long necked forms such as Hyphalosaurus and

13098-693: The Late Cretaceous-Early Palaeogene Cool Interval (LKEPCI). Tropical SSTs declined from around 35 °C in the early Campanian to around 28 °C in the Maastrichtian. Deep ocean temperatures declined to 9 to 12 °C, though the shallow temperature gradient between tropical and polar seas remained. Regional conditions in the Western Interior Seaway changed little between the MKH and

13275-642: The Ligurian Apennines are in Liguria . The etymology most frequently repeated, because of its semantic appropriateness, is that it derives from the Celtic penn , 'mountain', 'summit': A-penn-inus , which could have been assigned during the Celtic domination of north Italy in the 4th century BC or before. The name originally applied to the north Apennines. However historical linguists have never found

13452-556: The Lower Cretaceous Marne di Bruntino marl . The Po Valley is often regarded as a syncline , or dip in the crust due to compression at the edges. Regardless of whether this concept accurately describes its geology, the valley is manifestly a sediment-filled trough, or virtual syncline, continuous with the deeps of the Adriatic Sea . The surface terrain is therefore divided into two overall types of landform :

13629-720: The MKH. Mean annual temperatures at the poles during the MKH exceeded 14 °C. Such hot temperatures during the MKH resulted in a very gentle temperature gradient from the equator to the poles; the latitudinal temperature gradient during the Cenomanian-Turonian Thermal Maximum was 0.54 °C per ° latitude for the Southern Hemisphere and 0.49 °C per ° latitude for the Northern Hemisphere, in contrast to present day values of 1.07 and 0.69 °C per ° latitude for

13806-526: The MKH. The poles were so warm that ectothermic reptiles were able to inhabit them. Beginning in the Santonian, near the end of the MKH, the global climate began to cool, with this cooling trend continuing across the Campanian. This period of cooling, driven by falling levels of atmospheric carbon dioxide, caused the end of the MKH and the transition into a cooler climatic interval, known formally as

13983-457: The Maastrichtian, bucking the trend of overall cooler temperatures during the LKEPCI. Between 70 and 69 Ma and 66–65 Ma, isotopic ratios indicate elevated atmospheric CO 2 pressures with levels of 1000–1400 ppmV and mean annual temperatures in west Texas between 21 and 23 °C (70 and 73 °F). Atmospheric CO 2 and temperature relations indicate a doubling of pCO 2 was accompanied by

14160-653: The Mesozoic) ended with the Cretaceous–Paleogene extinction event , a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs , and large marine reptiles , died out, widely thought to have been caused by the impact of a large asteroid that formed the Chicxulub crater in the Gulf of Mexico. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary (K–Pg boundary),

14337-405: The Po Valley and the natural depressions on the right side of the Po River turned in vast swamp basins. The waterlogging process of the area continued until the 10th century influencing the human sustenance and settling practices. According to historical-archaeological data, indeed, the wetlands were exploited for fishing as well as for transport by boat while the early medieval sites settled on

14514-601: The Po Valley area, which incorporates the city of Milan , Turin , and Bologna . Milan and Turin share high levels of ozone and nitrogen oxides , which are mainly produced by cars' diesel and petrol engines. To shed light on the danger for humans living polluted environments, Chicago Energy Policy Institute has developed the Air Quality Life Index (AQLI), a system capable of analyzing air pollution worldwide. According to AQLI findings, Po valley air pollution affects inhabitants so hard that it cuts off about half

14691-667: The Po Valley during some of his brightest campaigns (1796 and 1800, culminating in the historical Battle of Marengo ), he found an advanced country and made it into his Kingdom of Italy . With Napoleon's final defeat the Austrians came back, but they were no longer welcome. In the west, in Piedmont , the Savoy dynasty would emerge to serve as a springboard for Italian unification. The Risorgimento , after an unsuccessful start in 1848 and 1849, triumphed ten years later in Lombardy , which

14868-521: The Po Valley reached its peak during the Renaissance (15th–16th centuries) and continued in the Modern Age (17th–18th centuries), with the last marsh areas only being reclaimed in the 20th century: channels and drainage system are still active and allow the Po Valley to be drained and be cultivatable. The Po Valley has a generally humid subtropical (Köppen: Cfa ) climate. The conformation of

15045-618: The Po Valley suffer the most serious impact at European level due to poor air quality, first of all the metropolitan area of Milan, thirteenth in the ranking in terms of fine particulate impact, where any year 3967 premature deaths occur – approximately 9% of the total. 45°19′49″N 9°47′56″E  /  45.33028°N 9.79889°E  / 45.33028; 9.79889 Apennine Mountains The Apennines or Apennine Mountains ( / ˈ æ p ə n aɪ n / AP -ə-nyne ; ‹See Tfd› Greek : Ἀπέννινα ὄρη or Ἀπέννινον ὄρος; Latin : Appenninus or Apenninus Mons   –

15222-510: The Po basin, has authority in several administrative regions of north Italy, including the plain north of the Adriatic and the territory south of the lower Po, as shown in the regional depiction included with this article. The law defines the Po basin as "the territory from which rainwater or snow and glacier melt flows on the surface, gathers in streams of water either directly or via tributaries...". The United Nations Environment Program includes

15399-847: The Riserva Naturale Statale Gola del Furlo, where Furlo Pass on the Via Flaminia is located. Both the Etruscans and the Romans constructed tunnels here. The Abruzzi Apennines, located in Abruzzo , Molise and southeastern Lazio , contain the highest peaks and most rugged terrain of the Apennines. They are known in history as the territory of the Italic peoples first defeated by the city of Rome . Coincidentally they exist in three parallel folds or chains surviving from

15576-527: The Romans used the Via Flaminia between Rome and Rimini . The montane distance between Florence in Tuscany and Bologna in Emilia-Romagna is shorter, but exploitation of it required the conquest of more rugged terrain, which was not feasible for the ancients. Railway lines were constructed over the mountains in the early 19th century but they were of low capacity and unimprovable. Since 1856,

15753-571: The Sele—joined by the Negro and Calore—on the west, and the Bradano , Basento , Agri, Sinni on the east, which flow into the gulf of Taranto; to the south of the last-named river there are only unimportant streams flowing into the sea east and west, inasmuch as here the width of the peninsula diminishes to some 64 kilometres (40 mi). The railway running south from Sicignano to Lagonegro, ascending

15930-541: The South Atlantic and Indian Oceans were newly formed. Such active rifting lifted great undersea mountain chains along the welts, raising eustatic sea levels worldwide. To the north of Africa the Tethys Sea continued to narrow. During most of the Late Cretaceous, North America would be divided in two by the Western Interior Seaway , a large interior sea, separating Laramidia to the west and Appalachia to

16107-570: The Southern and Northern hemispheres, respectively. This meant weaker global winds, which drive the ocean currents, and resulted in less upwelling and more stagnant oceans than today. This is evidenced by widespread black shale deposition and frequent anoxic events . Tropical SSTs during the late Albian most likely averaged around 30 °C. Despite this high SST, seawater was not hypersaline at this time, as this would have required significantly higher temperatures still. On land, arid zones in

16284-576: The Tethys to the Arctic Ocean and enabling biotic exchange between the two oceans. At the peak of the Cretaceous transgression , one-third of Earth's present land area was submerged. The Cretaceous is justly famous for its chalk ; indeed, more chalk formed in the Cretaceous than in any other period in the Phanerozoic . Mid-ocean ridge activity—or rather, the circulation of seawater through

16461-519: The Ticino River and are protected by a Biosphere Reserve. The Po Valley has had traces of inhabitation since at least 780,000 years ago, when the first big glaciation of pleistocene took place. Sites like Monte Poggiolo may have served as refuges of human populations fleeing the terribly cold conditions of northern Europe during the subsequent glaciations along pleistocene. The valley was covered by sea level in warm times, but glaciations could cause

16638-692: The Tuscan Apennines. They extend to the upper Tiber River . The highest point is Monte Cimone at 2,165 m (7,103 ft). A separate branch, the Apuan Alps , goes southwest, bordering the coast south of La Spezia . Whether they are to be considered part of the Apennines is a matter of opinion; certainly, they are part of the Apennine System. Topographically only the valley of the River Serchio , which running parallel to

16815-425: The ancestors of modern-day birds also diversified. They inhabited every continent, and were even found in cold polar latitudes. Pterosaurs were common in the early and middle Cretaceous, but as the Cretaceous proceeded they declined for poorly understood reasons (once thought to be due to competition with early birds , but now it is understood avian adaptive radiation is not consistent with pterosaur decline ). By

16992-522: The ancient name of Bologna . The Etruscan domination left significant marks and introduced urban civilisation, but was short-lived. Its inhabitants, the Venetics , likely being a distinct group who, being skillful merchants, were, in time, also culturally influenced by both Etruscans and Greeks . By 500 BC the Etruscans were gradually displaced from the region by migrating Gauls. By 196 BC, Rome

17169-580: The area, despite the destruction caused by Allied aerial bombing of many cities and heavy frontline fighting in Romagna . The Resistance protected the main industries, which the Third Reich was using for war production, preventing their destruction: on 25 April 1945 a general insurrection in the wake of the German defeat was a huge success. Most cities and towns, notably Milan and Turin, were freed by

17346-454: The best-preserved forests and montane grasslands in Europe, now protected by national parks and, within them, a high diversity of flora and fauna. These mountains are one of the last refuges of the big European predators such as the Italian wolf and the Marsican brown bear , now extinct in the rest of Central Europe . The mountains lend their name to the Apennine peninsula that forms

17523-476: The capital soon shifted from Verona to Pavia . Monza also was an important town in that time, more so than ruined Milan . The Lombards' harsh, caste -like rule over the natives softened somewhat with their conversion from Arianism to Catholicism . The Lombard kingdom was overthrown in 774 by Charlemagne and his Frankish armies, becoming a prized part of the Carolingian Empire , forming

17700-775: The central and eastern ranges are the valleys of Aquila and Sulmona . The chief rivers on the west are the Nera , with its tributaries the Velino and Salto, and the Aniene , both of which fall into the Tiber. On the east there is at first a succession of small rivers which flow into the Adriatic , from which the highest points of the chain are some 20   km distant, such as the Tronto , Tordino, Vomano and others. The Pescara , which receives

17877-593: The coast turns and exits into the Tyrrhenian Sea north of Pisa , separates the Apuan Alps from the Apennines; geologically the rock is of a slightly different composition, marble . The Roman marble industry was centered at Luna , and is now active in Carrara . As the Tuscan Apennines divide the peninsula between the Po Valley and the plains and hills of Tuscany and Lazio , transportation over them has been used to achieve political and economic unity. Historically

18054-408: The continental crust were covered with shallow seas. The Tethys Sea connecting the tropical oceans east to west also helped to warm the global climate. Warm-adapted plant fossils are known from localities as far north as Alaska and Greenland , while dinosaur fossils have been found within 15 degrees of the Cretaceous south pole . It was suggested that there was Antarctic marine glaciation in

18231-400: The drainage of wetlands. Land reclamations works profoundly modified many European regions. In Central Po Plain the earliest evidence of attempts to clear the forests and drain the wetlands is mentioned in historical documents from the late 8th century, but only from the 10th to 13th centuries were land and water management activities actually carried out widely. Further civil wars escalated in

18408-515: The earliest crown group birds. Acanthomorph fish, the most diverse group of modern vertebrates, appeared in aquatic habitats around the middle of the Cretaceous. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the end of the Cretaceous, coincident with the decline and extinction of previously widespread gymnosperm groups. The Cretaceous (along with

18585-544: The early and mid-Cretaceous (becoming extinct during the late Cretaceous Cenomanian-Turonian anoxic event ), plesiosaurs throughout the entire period, and mosasaurs appearing in the Late Cretaceous. Sea turtles in the form of Cheloniidae and Panchelonioidea lived during the period and survived the extinction event. Panchelonioidea is today represented by a single species; the leatherback sea turtle . The Hesperornithiformes were flightless, marine diving birds that swam like grebes . Baculites , an ammonite genus with

18762-494: The east, then receded late in the period, leaving thick marine deposits sandwiched between coal beds. Bivalve palaeobiogeography also indicates that Africa was split in half by a shallow sea during the Coniacian and Santonian, connecting the Tethys with the South Atlantic by way of the central Sahara and Central Africa, which were then underwater. Yet another shallow seaway ran between what is now Norway and Greenland, connecting

18939-747: The end of the AACS, which ended around 111 Ma with the Paquier/Urbino Thermal Maximum, giving way to the Mid-Cretaceous Hothouse (MKH), which lasted from the early Albian until the early Campanian. Faster rates of seafloor spreading and entry of carbon dioxide into the atmosphere are believed to have initiated this period of extreme warmth, along with high flood basalt activity. The MKH was punctuated by multiple thermal maxima of extreme warmth. The Leenhardt Thermal Event (LTE) occurred around 110 Ma, followed shortly by

19116-448: The end of the Cretaceous. The high sea level and warm climate of the Cretaceous meant large areas of the continents were covered by warm, shallow seas, providing habitat for many marine organisms. The Cretaceous was named for the extensive chalk deposits of this age in Europe, but in many parts of the world, the deposits from the Cretaceous are of marine limestone , a rock type that is formed under warm, shallow marine conditions. Due to

19293-463: The end of the period only three highly specialized families remained; Pteranodontidae , Nyctosauridae , and Azhdarchidae . The Liaoning lagerstätte ( Yixian Formation ) in China is an important site, full of preserved remains of numerous types of small dinosaurs, birds and mammals, that provides a glimpse of life in the Early Cretaceous. The coelurosaur dinosaurs found there represent types of

19470-407: The enlarged ridges—enriched the oceans in calcium ; this made the oceans more saturated, as well as increased the bioavailability of the element for calcareous nanoplankton . These widespread carbonates and other sedimentary deposits make the Cretaceous rock record especially fine. Famous formations from North America include the rich marine fossils of Kansas 's Smoky Hill Chalk Member and

19647-519: The entire Phanerozoic . The name is derived from the Latin creta , ' chalk ', which is abundant in the latter half of the period. It is usually abbreviated K , for its German translation Kreide . The Cretaceous was a period with a relatively warm climate , resulting in high eustatic sea levels that created numerous shallow inland seas . These oceans and seas were populated with now- extinct marine reptiles , ammonites , and rudists , while dinosaurs continued to dominate on land. The world

19824-528: The extinction fed on insects , larvae , worms , and snails, which in turn fed on dead plant and animal matter. Scientists theorise that these organisms survived the collapse of plant-based food chains because they fed on detritus . In stream communities , few groups of animals became extinct. Stream communities rely less on food from living plants and more on detritus that washes in from land. This particular ecological niche buffered them from extinction. Similar, but more complex patterns have been found in

20001-558: The first records of the gharial-like Neochoristodera , which appear to have evolved in the regional absence of aquatic neosuchian crocodyliformes. During the Late Cretaceous the neochoristodere Champsosaurus was widely distributed across western North America. Due to the extreme climatic warmth in the Arctic, choristoderans were able to colonise it too during the Late Cretaceous. In the seas, rays , modern sharks and teleosts became common. Marine reptiles included ichthyosaurs in

20178-475: The fluvial ridges, in topographically higher and strategic position in the surrounding swampy meadows. The Po Valley has been completely turned to agriculture since the Middle Ages , when efforts from monastic orders, feudal lords and free communes converged. The older and smaller cities deriving from ancient times are still located there. According to historical maps and documents the land reclamation of

20355-503: The genus Berriasella , but its use as a stratigraphic indicator has been questioned, as its first appearance does not correlate with that of C. alpina . The boundary is officially considered by the International Commission on Stratigraphy to be approximately 145 million years ago, but other estimates have been proposed based on U-Pb geochronology, ranging as young as 140 million years ago. The upper boundary of

20532-529: The government, much remains to be done. They also furnish considerable summer pastures, especially in the Abruzzi : Pliny ( Hist. Nat . xi. 240) praises the cheese of the Apennines. In the forests Italian wolves were frequent, and still are found, the flocks being protected against them by large sheep-dogs; Marsican brown bears , however, which were known in Roman times, have almost entirely disappeared. Nor are

20709-625: The group Maniraptora , which includes modern birds and their closest non-avian relatives, such as dromaeosaurs , oviraptorosaurs , therizinosaurs , troodontids along with other avialans . Fossils of these dinosaurs from the Liaoning lagerstätte are notable for the presence of hair-like feathers . Insects diversified during the Cretaceous, and the oldest known ants , termites and some lepidopterans , akin to butterflies and moths , appeared. Aphids , grasshoppers and gall wasps appeared. Rhynchocephalians (which today only includes

20886-412: The high sea level, there was extensive space for such sedimentation . Because of the relatively young age and great thickness of the system, Cretaceous rocks are evident in many areas worldwide. Chalk is a rock type characteristic for (but not restricted to) the Cretaceous. It consists of coccoliths , microscopically small calcite skeletons of coccolithophores , a type of algae that prospered in

21063-599: The highest death rate from fine particulate matter (PM 2.5 ) in Europe. Vicenza ( Veneto ) and Saronno (Lombardy) are in fourth and eighth place, respectively, in a top ten of ten cities. Turin and Milan are also at the top of the European ranking – 3rd and 5th respectively – in terms of increased mortality from nitrogen dioxide, a gas that is produced mainly from traffic and in particular from diesel vehicles, while Verona , Treviso , Padova , Como and Venice rank eleventh, fourteenth, fifteenth, seventeenth and twenty-third respectively. The data show that many cities in

21240-551: The highest rates of extinction and turnover. Thylacocephala , a class of crustaceans, went extinct in the Late Cretaceous. The first radiation of the diatoms (generally siliceous shelled, rather than calcareous ) in the oceans occurred during the Cretaceous; freshwater diatoms did not appear until the Miocene . Calcareous nannoplankton were important components of the marine microbiota and important as biostratigraphic markers and recorders of environmental change. The Cretaceous

21417-544: The hills; their pottery has been found on the Capitoline Hill in Rome as well as on the islands mentioned above. The Apennines are divided into three sectors: northern ( Appennino settentrionale ), central ( Appennino centrale ), and southern ( Appennino meridionale ). A number of long hiking trails wind through the Apennines. Of note is European walking route E1 coming from northern Europe and traversing

21594-589: The junction for Foggia, Spinazzola (for Barletta, Bari, and Taranto ) and Potenza. Roman roads followed the same lines as the railways: the Via Appia ran from Capua to Benevento, whence the older road went to Venosa and Taranto and so to Brindisi , while the Via Traiana ran nearly to Troia (near Foggia) and thence to Bari. The valley of the Ofanto , which runs into the Adriatic close to Barletta , marks

21771-770: The last epoch of the Jurassic, the Tithonian, continued into the Berriasian, the first age of the Cretaceous. The North Atlantic seaway opened and enabled the flow of cool water from the Boreal Ocean into the Tethys. There is evidence that snowfalls were common in the higher latitudes during this age, and the tropics became wetter than during the Triassic and Jurassic. Glaciation was restricted to high- latitude mountains, though seasonal snow may have existed farther from

21948-575: The late Valanginian (~ 134 million years ago) found in Israel and Italy, initially at low abundance. Molecular clock estimates conflict with fossil estimates, suggesting the diversification of crown-group angiosperms during the Late Triassic or the Jurassic, but such estimates are difficult to reconcile with the heavily sampled pollen record and the distinctive tricolpate to tricolporoidate (triple grooved) pollen of eudicot angiosperms. Among

22125-465: The late Cretaceous, and all else that depended on them suffered, as well. Herbivorous animals, which depended on plants and plankton as their food, died out as their food sources became scarce; consequently, the top predators , such as Tyrannosaurus rex , also perished. Yet only three major groups of tetrapods disappeared completely; the nonavian dinosaurs , the plesiosaurs and the pterosaurs . The other Cretaceous groups that did not survive into

22302-574: The latest Albian. Approximately 94 Ma, the Cenomanian-Turonian Thermal Maximum occurred, with this hyperthermal being the most extreme hothouse interval of the Cretaceous and being associated with a sea level highstand. Temperatures cooled down slightly over the next few million years, but then another thermal maximum, the Coniacian Thermal Maximum, happened, with this thermal event being dated to around 87 Ma. Atmospheric CO 2 levels may have varied by thousands of ppm throughout

22479-579: The lengths of the northern and central Apennines. The Grand Italian Trail begins in Trieste and after winding through the Alpine arc traverses the entire Apennine system, Sicily and Sardinia. The northern Apennines consist of three subchains : the Ligurian ( Appennino ligure ), Tuscan-Emilian ( Appennino tosco-emiliano ), and Umbrian Apennines ( Appennino umbro ). The Ligurian Apennines border

22656-421: The l’Arboudeyesse Thermal Event (ATE) a million years later. Following these two hyperthermals was the Amadeus Thermal Maximum around 106 Ma, during the middle Albian. Then, around a million years after that, occurred the Petite Verol Thermal Event (PVTE). Afterwards, around 102.5 Ma, the Event 6 Thermal Event (EV6) took place; this event was itself followed by the Breistroffer Thermal Maximum around 101 Ma, during

22833-448: The major part of Italy. They are mostly verdant, although one side of the highest peak, Corno Grande , is partially covered by Calderone glacier , the only glacier in the Apennines. The eastern slopes down to the Adriatic Sea are steep, whilst the western slopes form foothills on which most of the towns of peninsular Italy are located. The mountains tend to be named after the province or provinces in which they are located; for example

23010-409: The middle Cretaceous, becoming the dominant group of land plants by the end of the period, coincident with the decline of previously dominant groups such as conifers. The oldest known fossils of grasses are from the Albian , with the family having diversified into modern groups by the end of the Cretaceous. The oldest large angiosperm trees are known from the Turonian (c. 90 Mya) of New Jersey, with

23187-403: The most modern techniques available. The population averaged some 50 people per square kilometer, a very high standard for those times. In 1494, the ruinous Italian Wars began between France and Spain , which lasted for decades. Land changed hands frequently. Even Switzerland received some Italian-speaking lands in the north ( Canton Ticino , not technically a part of the Padan region), and

23364-408: The most promising candidates for fixing the Jurassic–Cretaceous boundary. In particular, the first appearance Calpionella alpina , coinciding with the base of the eponymous Alpina subzone, has been proposed as the definition of the base of the Cretaceous. The working definition for the boundary has often been placed as the first appearance of the ammonite Strambergella jacobi , formerly placed in

23541-446: The mountains bend away to the southeast. The upper Bormida can be reached by a number of roads proceeding inland at a right angle to the coast southwest of Savona , the chief one being the Autostrada Torino-Savona. They ascend to the Bocchetta di Altare , sometimes called Colle di Cadibona , 436 m (1,430 ft), the border between the Ligurian Alps along the coast to the west and the Ligurian Apennines. A bronze plaque fixed to

23718-474: The name. This view has the word originating in Latium inconsistently with the theory of the northern origin. None of these derivations is accepted unquestionably. The Apennine culture is a technology complex in central and southern Italy from the Italian Middle Bronze Age (15th–14th centuries BC). In the mid-20th century the Apennine was divided into Proto-, Early, Middle and Late sub- phases , but now archaeologists prefer to consider as "Apennine" only

23895-402: The north and the Abruzzi Apennines ( Appennino abruzzese ) in the south. It extends from Bocca Serriola pass in the north to Forlì pass in the south. The west border of the Umbria-Marche Apennines (or Appennino umbro-marchigiano )) runs through Cagli . They extend south to the Tronto River, the south border of the ONA. The highest peak, Monte Vettore , at 2,478 m (8,130 ft),

24072-476: The north, among the many streams that empty into the north Adriatic from the west and north. Geo-political definitions of the valley depend on the defining authority. The Po Basin Water Board ( Italian : Autorità di bacino del fiume Po ), authorized in 1989 by Law no. 183/89 to oversee "protection of lands, water rehabilitation, the use and management of hydro resources for the national economic and social development, and protection of related environment" within

24249-405: The north. The Po Valley and the Adriatic overlay a foreland basin and a system of deeply buried ancient canyons surviving from the tectonic collision of an offshore land mass, Tyrrhenis, with the mainland, an incident within the collision of the African and Eurasian plates. Since the Messinian (7–5 mya ) the system has been filling with sediment mainly from the older Apennines but also from

24426-466: The northern termination of the first range of the Lucanian Apennines (now Basilicata ), which runs from east to west, while south of the valleys of the Sele (on the west) and Basento (on the east)—which form the line followed by the railway from Battipaglia via Potenza to Metaponto —the second range begins to run due north and south as far as the plain of Sibari . The highest point is the Monte Pollino 2,233 metres (7,325 ft). The chief rivers are

24603-824: The oceans. Extinction was more severe among animals living in the water column than among animals living on or in the seafloor. Animals in the water column are almost entirely dependent on primary production from living phytoplankton, while animals living on or in the ocean floor feed on detritus or can switch to detritus feeding. The largest air-breathing survivors of the event, crocodilians and champsosaurs , were semiaquatic and had access to detritus. Modern crocodilians can live as scavengers and can survive for months without food and go into hibernation when conditions are unfavorable, and their young are small, grow slowly, and feed largely on invertebrates and dead organisms or fragments of organisms for their first few years. These characteristics have been linked to crocodilian survival at

24780-414: The oldest records of Angiosperm macrofossils are Montsechia from the Barremian aged Las Hoyas beds of Spain and Archaefructus from the Barremian-Aptian boundary Yixian Formation in China. Tricolpate pollen distinctive of eudicots first appears in the Late Barremian, while the earliest remains of monocots are known from the Aptian. Flowering plants underwent a rapid radiation beginning during

24957-566: The ornamental pottery style of the later phase of Middle Bronze Age (BM3). This phase is preceded by the Grotta Nuova facies (central Italy) and by the Protoapennine B facies (southern Italy) and succeeded by the Subapennine facies of 13th-century ("Bronzo Recente"). Apennine pottery is a burnished ware incised with spirals, meanders and geometrical zones, filled with dots or transverse dashes. It has been found on Ischia island in association with LHII and LHIII pottery and on Lipari in association with LHIIIA pottery, which associations date it to

25134-418: The partisans days before the Allies arrived. After the war, the Padan area took the lead in the economic miracle of the 1950s and 60s. Since 1989, Lega Nord , a federation of Northern regionalist parties, has promoted either secession or larger autonomy for the Padan area which they call Padania . The Po Valley is one of the most important industrial and agricultural areas in Europe. Hydroelectricity

25311-400: The plain, or flat surface of the fill, and the anticline at the edges, taking the form of hilly country in which the outcrops of the original rock are visible along with alluvial fans formed from the outwash of the more severe anticlinal terrain; that is, the Apennines and the Alps. The valley is broadly divided into an upper, drier part, often not particularly suited for agriculture, and

25488-532: The plain, surrounded by the Alps and the Apennines , and the influence of the Adriatic Sea cause high levels of relative humidity throughout the year. The climate is increasingly warmer and more humid farther south and east. Winters are cool and damp, with January mean temperatures ranging between 0 and 5 °C (32 and 41 °F). Fog and mist are frequent, although the urban heat effect has made winters less foggy and cold than before in some areas. Snow and winter droughts can deny sufficient moisture to

25665-427: The poles. After the end of the first age, however, temperatures began to increase again, with a number of thermal excursions, such as the middle Valanginian Weissert Thermal Excursion (WTX), which was caused by the Paraná-Etendeka Large Igneous Province's activity. It was followed by the middle Hauterivian Faraoni Thermal Excursion (FTX) and the early Barremian Hauptblatterton Thermal Event (HTE). The HTE marked

25842-412: The principal food of mosasaurs , a group of giant marine lizards related to snakes that became extinct at the boundary. Omnivores , insectivores , and carrion -eaters survived the extinction event, perhaps because of the increased availability of their food sources. At the end of the Cretaceous, there seem to have been no purely herbivorous or carnivorous mammals . Mammals and birds that survived

26019-455: The punctuation mark at the end of a progressive decline in biodiversity during the Maastrichtian age. The result was the extinction of three-quarters of Earth's plant and animal species. The impact created the sharp break known as the K–Pg boundary (formerly known as the K–T boundary). Earth's biodiversity required substantial time to recover from this event, despite the probable existence of an abundance of vacant ecological niches . Despite

26196-411: The region's history by adding the Po Valley to the Holy Roman Empire of the Germanic nation in 962. In Veneto , the lagoon capital of Venice , emerged a great sea power in alliance with its old master, the Byzantine Empire . In time the Comuni emerged, as towns thrived in commerce. Soon Milan became the most powerful city of the central plain of Lombardy proper, and despite being razed in 1162, it

26373-744: The rise of angiosperms, during the Jurassic and the Early Cretaceous, the higher flora was dominated by gymnosperm groups, including cycads , conifers , ginkgophytes , gnetophytes and close relatives, as well as the extinct Bennettitales . Other groups of plants included pteridosperms or "seed ferns", a collective term that refers to disparate groups of extinct seed plants with fern-like foliage, including groups such as Corystospermaceae and Caytoniales . The exact origins of angiosperms are uncertain, although molecular evidence suggests that they are not closely related to any living group of gymnosperms. The earliest widely accepted evidence of flowering plants are monosulcate (single-grooved) pollen grains from

26550-568: The river's origin in the southern Piedmontese province of Cuneo , also known as the Provincia granda . The valley is crossed by a number of affluents running down from the Alps in the north and from the Apennines in the south. The Po's major affluents include the Tanaro , Scrivia , Trebbia , Panaro and Secchia in the south, Dora Riparia , Dora Baltea , Sesia , Ticino (draining Lake Maggiore ), Lambro , Adda (draining Lake Como ), Oglio (draining Lake Iseo ) and Mincio (draining Lake Garda and called Sarca in its upper reaches) in

26727-430: The sea, occurs on the east coast, extending halfway across the peninsula. Here the limestone Apennines proper cease and the granite mountains of Calabria begin. The first group extends as far as the isthmus formed by the gulfs of South Eufemia and Squillace; it is known as the Sila, and the highest point reached is 1,930 metres (6,330 ft) (the Botte Donato ). The forests which covered it in ancient times supplied

26904-400: The severity of the K-Pg extinction event, there were significant variations in the rate of extinction between and within different clades . Species that depended on photosynthesis declined or became extinct as atmospheric particles blocked solar energy . As is the case today, photosynthesizing organisms, such as phytoplankton and land plants , formed the primary part of the food chain in

27081-402: The soil for agriculture. Summers are hot and humid, with July mean temperatures ranging between 22 and 25 °C (72 and 77 °F) (1971–2000 averages). Frequent thunderstorms and sudden hailstorms can produce large hail, dump large quantities of rain, and destroy crops. Supercell thunderstorms produce large hail, with significant agricultural costs. Tornadoes are common in the plains of

27258-445: The stake became common practice during witchhunts , especially in the neighboring Alpine lands. During this bleak period, however, Lombard industry recovered, especially the textile branch, its pillar. When the War of Spanish Succession traded Milan to Austria , government and administration improved significantly. Though the peasantry began a century-long plunge into misery, cities prospered and grew. When Napoleon I entered

27435-401: The state railway system, highly developed on the coastal plain, now traverses the mountains routinely through a number of railway tunnels, such as the one at Giovi Pass . The southeastern border of the Ligurian Apennines is the Fiume Magra , which projects into the Tyrrhenian Sea south of La Spezia , and the Fiume Taro , which runs in the opposite direction to join the Po. The divide between

27612-422: The strong regionality of most biostratigraphic markers, and the lack of any chemostratigraphic events, such as isotope excursions (large sudden changes in ratios of isotopes ) that could be used to define or correlate a boundary. Calpionellids , an enigmatic group of planktonic protists with urn-shaped calcitic tests briefly abundant during the latest Jurassic to earliest Cretaceous, have been suggested as

27789-404: The terrestrial fauna of the late Cretaceous Hell Creek Formation . Other important Cretaceous exposures occur in Europe (e.g., the Weald ) and China (the Yixian Formation ). In the area that is now India, massive lava beds called the Deccan Traps were erupted in the very late Cretaceous and early Paleocene. Palynological evidence indicates the Cretaceous climate had three broad phases:

27966-458: The thick forests and swamps were the Ligurians , who may have been an Indo-European people. After the progressive immigration in the 7th century BC of Celtic peoples known as the Insubres (hence the name of Insubria sometimes being given to northwestern Lombardy ), the southern and central regions were conquered and colonised here and there by a pre-Indo-European people, the Etruscans , who left names such as Parma , Ravenna and Felsina,

28143-407: The three parallel chains are broken up into smaller groups; among them may be named the Matese , the highest point of which is the Monte Miletto 2,050 metres (6,725 ft). The chief rivers on the south-west are the Liri or Garigliano with its tributary the Sacco, the Volturno , Sebeto, Sarno, on the north the Trigno, Biferno and Fortore . Daunian mountains , in Apulia , are connected with

28320-483: The trunk having a preserved diameter of 1.8 metres (5.9 ft) and an estimated height of 50 metres (160 ft). During the Cretaceous, ferns in the order Polypodiales , which make up 80% of living fern species, would also begin to diversify. On land, mammals were generally small sized, but a very relevant component of the fauna , with cimolodont multituberculates outnumbering dinosaurs in some sites. Neither true marsupials nor placentals existed until

28497-426: The two upper river valleys is the Cisa Pass . Under it (in two tunnels) runs the Autostrada della Cisa between Spezia and Parma . Starting at Cisa Pass , the mountain chain turns further to the southeast, to cross the peninsula along the border between the Emilia-Romagna and Tuscany regions. They are named the Tuscan–Emilian Apennines west of the Futa Pass and the Tuscan–Romagnol Apennines east of it, or just

28674-490: The ultimate end of the Tithonian-early Barremian Cool Interval (TEBCI). During this interval, precession was the dominant orbital driver of environmental changes in the Vocontian Basin. For much of the TEBCI, northern Gondwana experienced a monsoonal climate. A shallow thermocline existed in the mid-latitude Tethys. The TEBCI was followed by the Barremian-Aptian Warm Interval (BAWI). This hot climatic interval coincides with Manihiki and Ontong Java Plateau volcanism and with

28851-413: The upper Cretaceous of Western Europe . The name Cretaceous was derived from the Latin creta , meaning chalk . The twofold division of the Cretaceous was implemented by Conybeare and Phillips in 1822. Alcide d'Orbigny in 1840 divided the French Cretaceous into five étages (stages): the Neocomian , Aptian, Albian, Turonian, and Senonian, later adding the Urgonian between Neocomian and Aptian and

29028-415: The valley of the Aterno to Sulmona. In ancient times the Via Salaria , Via Caecilia and Via Tiburtina all ran from Rome to the Adriatic coast . The volcanic mountains of the province of Rome are separated from the Apennines by the Tiber valley, and the Monti Lepini , part of the Volscian chain, by the valleys of the Sacco and Liri . In the southern Apennines, to the south of the Sangro valley,

29205-417: The valley of the Negro, is planned to extend to Cosenza, along the line followed by the ancient Via Popilia, which beyond Cosenza reached the west coast at Terina and thence followed it to Reggio. The Via Herculia  [ it ] , a branch of the Via Traiana , ran from Aequum Tuticum to the ancient Nerulum . At the narrowest point the plain of Sibari, through which the rivers Coscile and Crati flow to

29382-472: The valley. The Friuli-Venezia Giulia ,beyond the Po River plain itself, is downwind of the mountains and upwind of moisture sources from nearby is an exception. Spring and autumn are well-marked and pleasant. Both winter and summer are less mild in the lower parts along the Po, while the Adriatic Sea and the great lakes moderate the local climate in their proximity. Rainfall varies between 700 and 1,200 mm (30 and 45 inches) and equally distributed during

29559-628: The very end, but a variety of non-marsupial metatherians and non-placental eutherians had already begun to diversify greatly, ranging as carnivores ( Deltatheroida ), aquatic foragers ( Stagodontidae ) and herbivores ( Schowalteria , Zhelestidae ). Various "archaic" groups like eutriconodonts were common in the Early Cretaceous, but by the Late Cretaceous northern mammalian faunas were dominated by multituberculates and therians , with dryolestoids dominating South America . The apex predators were archosaurian reptiles , especially dinosaurs , which were at their most diverse stage. Avians such as

29736-419: The water of which is both drunk on the spot and sold as table water elsewhere. The Apennines are home to twelve Italian national parks : the Appennino Tosco-Emiliano National Park , the Foreste Casentinesi, Monte Falterona, Campigna National Park , the Monti Sibillini National Park , the Gran Sasso e Monti della Laga National Park , the Abruzzo, Lazio and Molise National Park , the Maiella National Park ,

29913-404: The wild goats called rotae , spoken of by Marcus Terentius Varro ( Rerum rusticarum II. i. 5), which may have been either Pyrenean chamois or steinbock , to be found. Brigandage appears to have been prevalent in Roman times in the more remote parts of the Apennines, as it was until recently. An inscription found near the Furlo pass was set up in AD 246 by an evocatus Augusti (a member of

30090-407: The world, alternative local subdivisions are still in use. From youngest to oldest, the subdivisions of the Cretaceous period are: The lower boundary of the Cretaceous is currently undefined, and the Jurassic–Cretaceous boundary is currently the only system boundary to lack a defined Global Boundary Stratotype Section and Point (GSSP). Placing a GSSP for this boundary has been difficult because of

30267-606: The year. Rainfall maximums are during autumn and spring. Winds are usually weak, although sudden bursts of foehn or thunderstorms can sweep the air clean. The almost enclosed nature of the Padan basin with much road traffic, makes it prone to a high level of pollution in winter, when cold air clings to the soil . The natural potential vegetation of the Po basin is a mixed broadleaf forest of pedunculate oak , poplars , European hornbeam , alders , elderberry , elms , willows , maples , ash , and other central-European trees. The largest remaining fragments of forest are located around

30444-424: Was a Milan-driven Lombard League with Papal benediction that defeated emperor Frederick Barbarossa at the Battle of Legnano in 1176. Between the 10th and 13th centuries, concurrent with the Medieval Warm Period climate phase, the European population grew substantially, almost tripling (in Northern and Central Italy, the urban population doubled), and increasing the demand for cultivated lands. Cereals became

30621-457: Was conquered by a Franco-Piedmontese army. In 1866 Veneto joined young Italy, thanks to Prussia 's defeat of Austria . Poverty in the countryside increased emigration to the Americas , a phenomenon which subsided in the central region towards the end of the 19th century, but persisted in Veneto well into the 20th century. Industry grew rapidly, thanks to an abundance of water and literate manpower. The World Wars did not significantly damage

30798-450: Was followed by the Aptian-Albian Cold Snap (AACS) that began about 118 Ma. A short, relatively minor ice age may have occurred during this so-called "cold snap", as evidenced by glacial dropstones in the western parts of the Tethys Ocean and the expansion of calcareous nannofossils that dwelt in cold water into lower latitudes. The AACS is associated with an arid period in the Iberian Peninsula . Temperatures increased drastically after

30975-454: Was largely ice-free, although there is some evidence of brief periods of glaciation during the cooler first half, and forests extended to the poles. Many of the dominant taxonomic groups present in modern times can be ultimately traced back to origins in the Cretaceous. During this time, new groups of mammals and birds appeared, including the earliest relatives of placentals & marsupials ( Eutheria and Metatheria respectively), and

31152-407: Was master of the woody plains and soon displaced the Etruscans, dotting the region with bustling colonies, clearing the land, fighting the last rebel tribes and gradually imposing its own civilisation. The Gothic War and Justinian's plague devastated the Padan population. In this scenario of desolation, from which many people had fled to the mountains for safety (making them fairly populated till

31329-402: Was opened after many years of construction consisting of major tunnels (the longest being the new 8.6-kilometre (5.3-mile) 'Tunel Base') and new overpasses, shortening the traveling time between Florence and Bologna by road. The Foreste Casentinesi, Monte Falterona, Campigna National Park is in the southern part of the Tuscan–Romagnol Apennines. The southern limit of the Tuscan–Romagnol Apennines

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