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67-718: St Alouarn Islands are a group of islands and rocks south-east of Cape Leeuwin in Western Australia , approximately 11 km south of Augusta in Flinders Bay . In March 1772, the crew of the French naval vessel Le Gros Ventre , commanded by Louis Aleno de St Aloüarn , became the first Europeans known to have visited the islands. A few weeks later, at Dirk Hartog Island , St Aloüarn formally claimed part of Western Australia for France . The islands were named after St Aloüarn in 1792, by Antoine d'Entrecasteaux , as

134-402: A rescue service , if necessary. Improvements in maritime navigation and safety, such Global Positioning System (GPS), led to the phasing out of non-automated lighthouses across the world. Although several closed due to safety concerns, Canada still maintains 49 staffed lighthouses, split roughly evenly across east and west coasts. The remaining modern lighthouses are usually illuminated by

201-466: A substrate , to absorb the gas, allowing the gas to be stored, and hence used, safely. Dalén also invented the ' sun valve ', which automatically regulated the light and turned it off during the daytime. The technology was the predominant light source in lighthouses from the 1900s to the 1960s, when electric lighting had become dominant. With the development of the steady illumination of the Argand lamp,

268-724: A 1627 map by Hessel Gerritsz : Caert van't Landt van d'Eendracht ("Chart of the Land of Eendracht"), which appears to show the coast between present-day Hamelin Bay and Point D'Entrecasteaux. Cape Leeuwin itself cannot be recognised. Other European vessels passed by for the next two centuries, including the Dutch ' t Gulden Zeepaert , commanded by François Thijssen , in 1627 and the French Gros Ventre , under Louis Aleno de St Aloüarn , in 1772. The first known European sighting of

335-640: A Diesel generator for backup. Many Fresnel lens installations have been replaced by rotating aerobeacons , which require less maintenance. In modern automated lighthouses, the system of rotating lenses is often replaced by a high intensity light that emits brief omnidirectional flashes, concentrating the light in time rather than direction. These lights are similar to obstruction lights used to warn aircraft of tall structures. Later innovations were "Vega Lights", and experiments with light-emitting diode (LED) panels. LED lights, which use less energy and are easier to maintain, had come into widespread use by 2020. In

402-510: A few named rocks in the group Unnamed rocks run parallel to the line of named islands above, between Cape Leeuwin and South-West Breaker, with one exception - Spout Rock , west of Flinders Islet. In 2009, the gazettal of the Augusta Port Area delineated the port in reference to the northernmost point (at High water level) on Saint Alouarn Island (with truncated spelling), as well as Seal Island, and Point Matthew. In 2013 - 2013,

469-436: A filament source. Experimental installations of laser lights, either at high power to provide a "line of light" in the sky or, utilising low power, aimed towards mariners have identified problems of increased complexity in installation and maintenance, and high power requirements. The first practical installation, in 1971 at Point Danger lighthouse , Queensland , was replaced by a conventional light after four years, because

536-414: A horizontal plane, and horizontally the light is focused into one or a few directions at a time, with the light beam swept around. As a result, in addition to seeing the side of the light beam, the light is directly visible from greater distances, and with an identifying light characteristic . This concentration of light is accomplished with a rotating lens assembly. In early lighthouses, the light source

603-466: A lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. A Fresnel lens can also capture more oblique light from a light source, thus allowing the light from a lighthouse equipped with one to be visible over greater distances. The first Fresnel lens was used in 1823 in the Cordouan lighthouse at the mouth of

670-427: A more powerful hyperradiant Fresnel lens manufactured by the firm of Chance Brothers . While lighthouse buildings differ depending on the location and purpose, they tend to have common components. A light station comprises the lighthouse tower and all outbuildings, such as the keeper's living quarters, fuel house, boathouse, and fog-signaling building. The Lighthouse itself consists of a tower structure supporting

737-602: A navigator with a line of position called a range in North America and a transit in Britain. Ranges can be used to precisely align a vessel within a narrow channel such as a river. With landmarks of a range illuminated with a set of fixed lighthouses, nighttime navigation is possible. Such paired lighthouses are called range lights in North America and leading lights in the United Kingdom. The closer light

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804-521: A number of screw-pile lighthouses. Englishman James Douglass was knighted for his work on the fourth Eddystone Lighthouse. United States Army Corps of Engineers Lieutenant George Meade built numerous lighthouses along the Atlantic and Gulf coasts before gaining wider fame as the winning general at the Battle of Gettysburg . Colonel Orlando M. Poe , engineer to General William Tecumseh Sherman in

871-402: A particular color (usually formed by colored panes in the lantern) to distinguish safe water areas from dangerous shoals. Modern lighthouses often have unique reflectors or racon transponders so the radar signature of the light is also unique. Before modern strobe lights , lenses were used to concentrate the light from a continuous source. Vertical light rays of the lamp are redirected into

938-415: A single stationary flashing light powered by solar-charged batteries and mounted on a steel skeleton tower. Where the power requirement is too great for solar power alone, cycle charging of the battery by a Diesel generator is provided. The generator only comes into use when the battery needs charging, saving fuel and increasing periods between maintenance. John Smeaton is noteworthy for having designed

1005-540: Is warm-summer Mediterranean ( Csb in the Köppen climate classification ), with an average annual rainfall of around 954 millimetres (37.6 in). Most rain falls between May and August, when around two days in three record measurable rainfall and around one in ten over 10 millimetres (0.39 in). During the summer, the weather is warm, though there are usually sea breezes , and frequently sunny. The dry summers, coupled with strong winds, creates an environment where there

1072-424: Is always a high risk of bush fires . The hillside to the west of the lighthouse, and the land nearby is now part of Leeuwin-Naturaliste National Park . It has extensive heath vegetation and thick scrub which supports a very high number of plant species and also bird species that utilise this habitat. The bay just east of Cape Leeuwin is Flinders Bay , named after Matthew Flinders , the circumnavigating explorer of

1139-419: Is one example. Race Rocks Light in western Canada is painted in horizontal black and white bands to stand out against the horizon. For effectiveness, the lamp must be high enough to be seen before the danger is reached by a mariner. The minimum height is calculated by trigonometry (see Distance to the horizon ) as D = 1.22 H {\displaystyle D=1.22{\sqrt {H}}} , where H

1206-510: Is the height above water in feet, and D is the distance from the lighthouse to the horizon in nautical miles, the lighthouse range . Where dangerous shoals are located far off a flat sandy beach, the prototypical tall masonry coastal lighthouse is constructed to assist the navigator making a landfall after an ocean crossing. Often these are cylindrical to reduce the effect of wind on a tall structure, such as Cape May Light . Smaller versions of this design are often used as harbor lights to mark

1273-548: The Cape Leeuwin Lighthouse in daylight hours. Whale watching boats leaving from Augusta Port tend not to venture into this group of islands and rocks, but travel around Flinders Bay to the east of the islands. The islands are significant for their bird colonies - with Seal Island and St Alouarn Island being reserves for that purpose. The named islands, in order of distance from mainland are: (also identified by some sources as Flinders Island There are

1340-622: The Florida Reef along the Florida Keys, beginning with the Carysfort Reef Light in 1852. In waters too deep for a conventional structure, a lightship might be used instead of a lighthouse, such as the former lightship Columbia . Most of these have now been replaced by fixed light platforms (such as Ambrose Light ) similar to those used for offshore oil exploration . Aligning two fixed points on land provides

1407-481: The Gironde estuary ; its light could be seen from more than 20 miles (32 km) out. Fresnel's invention increased the luminosity of the lighthouse lamp by a factor of four and his system is still in common use. The introduction of electrification and automatic lamp changers began to make lighthouse keepers obsolete. For many years, lighthouses still had keepers, partly because lighthouse keepers could serve as

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1474-473: The St Alouarn Islands , extend further in Flinders Bay to the east of the cape. The nearest settlement, north of the cape, is Augusta . South-east of Cape Leeuwin, the coast of Western Australia extends much further south. Cape Leeuwin is not the southernmost point of Western Australia, with that distinction belonging to West Cape Howe , which is to the southeast, near Albany . In Australia,

1541-539: The 1890s and 1930s subsequently left the bay with no port facility. 34°24′S 115°12′E  /  34.400°S 115.200°E  / -34.400; 115.200 Cape Leeuwin Cape Leeuwin / ˈ l uː w ɪ n / is the most south-westerly (but not most southerly) mainland point of the Australian continent , in the state of Western Australia . A few small islands and rocks,

1608-513: The 20th century. These often have a narrow cylindrical core surrounded by an open lattice work bracing, such as Finns Point Range Light . Sometimes a lighthouse needs to be constructed in the water itself. Wave-washed lighthouses are masonry structures constructed to withstand water impact, such as Eddystone Lighthouse in Britain and the St. George Reef Light of California. In shallower bays, Screw-pile lighthouse ironwork structures are screwed into

1675-456: The Romans, and developed a technique of securing the granite blocks together using dovetail joints and marble dowels . The dovetailing feature served to improve the structural stability , although Smeaton also had to taper the thickness of the tower towards the top, for which he curved the tower inwards on a gentle gradient. This profile had the added advantage of allowing some of the energy of

1742-405: The United Kingdom and Ireland about a third of lighthouses had been converted from filament light sources to use LEDs, and conversion continued with about three per year. The light sources are designed to replicate the colour and character of the traditional light as closely as possible. The change is often not noticed by people in the region, but sometimes a proposed change leads to calls to preserve

1809-775: The Western Australian government, through the Royalties for Regions programme, constructed a new harbour outside of the Hardy Inlet area of the Blackwood River mouth. The port is to the south, and within view of Flinders Bay settlement and boat ramp. It is located adjacent to the road that goes to Cape Leeuwin lighthouse. Oceangoing vessels had previously anchored in Flinders Bay, or used the Flinders Bay jetty; however, its short-term operation between

1876-510: The age. This structure was based upon Smeaton's design, but with several improved features, such as the incorporation of rotating lights, alternating between red and white. Stevenson worked for the Northern Lighthouse Board for nearly fifty years during which time he designed and oversaw the construction and later improvement of numerous lighthouses. He innovated in the choice of light sources, mountings, reflector design,

1943-439: The application of optical lenses to increase and focus the light intensity became a practical possibility. William Hutchinson developed the first practical optical system in 1777, known as a catoptric system. This rudimentary system effectively collimated the emitted light into a concentrated beam, thereby greatly increasing the light's visibility. The ability to focus the light led to the first revolving lighthouse beams, where

2010-491: The beam was too narrow to be seen easily. In any of these designs an observer, rather than seeing a continuous weak light, sees a brighter light during short time intervals. These instants of bright light are arranged to create a light characteristic or pattern specific to a lighthouse. For example, the Scheveningen Lighthouse flashes are alternately 2.5 and 7.5 seconds. Some lights have sectors of

2077-604: The cape is considered where the Indian Ocean meets the Southern Ocean , but most other nations and bodies consider that the Southern Ocean exists only south of 60°S . Located on headland of the cape is the Cape Leeuwin Lighthouse and the buildings that were used by the lighthouse -keepers. Cape Leeuwin is considered one of the three " great capes " of the world. Cape Leeuwin is often grouped with

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2144-470: The cape was by Antoine Bruni d'Entrecasteaux in 1791. d'Entrecasteaux thought the cape was an island, and named it "Isle St Allouarn" ("St Allouarn Island"), in honour of Captain de St Aloüarn. Ten years later, Matthew Flinders began his survey of the South coast of New Holland from Cape Leeuwin in 1801 when he named it. Flinders landed in the bay to the east of Cape Leeuwin, today's Flinders Bay . Flinders

2211-442: The cape's correct pronunciation; to rhyme with "flew in". Lighthouse Lighthouses mark dangerous coastlines, hazardous shoals , reefs , rocks, and safe entries to harbors; they also assist in aerial navigation . Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and the advent of much cheaper, more sophisticated, and more effective electronic navigational systems. Before

2278-533: The collapse of the Soviet government in 1990s, most of the official records on the locations, and condition, of these lighthouses were reportedly lost. Over time, the condition of RTGs in Russia degraded; many of them fell victim to vandalism and scrap metal thieves, who may not have been aware of the dangerous radioactive contents. Energy-efficient LED lights can be powered by solar panels , with batteries instead of

2345-457: The development of clearly defined ports , mariners were guided by fires built on hilltops. Since elevating the fire would improve visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs and promontories , unlike many modern lighthouses. The most famous lighthouse structure from antiquity

2412-559: The early 19th century. Shipwrecks within sight of this location include SS  Pericles , an iron-screw steamer built in Belfast in Northern Ireland , which sank after hitting an uncharted rock on a clear calm day in 1910. The wreck was found by Tom Snider in 1957 at 34°25.33′S 115°08.24′E  /  34.42217°S 115.13733°E  / -34.42217; 115.13733  ( SS Pericles ) . He dived on

2479-475: The entrance into a harbor, such as New London Harbor Light . Where a tall cliff exists, a smaller structure may be placed on top such as at Horton Point Light . Sometimes, such a location can be too high, for example along the west coast of the United States, where frequent low clouds can obscure the light. In these cases, lighthouses are placed below the clifftop to ensure that they can still be seen at

2546-512: The first peoples in the area. They called it "Doogalup". The English navigator Matthew Flinders named Cape Leeuwin after the first known ship to have visited the area, the Leeuwin ("Lioness"), a Dutch vessel that charted some of the nearby coastlines in 1622. The log of the Leeuwin has been lost, so very little is known of the voyage. However, the land found by the Leeuwin was recorded on

2613-455: The lantern room where the light operates. The lantern room is the glassed-in housing at the top of a lighthouse tower containing the lamp and lens. Its glass storm panes are supported by metal muntins (glazing bars) running vertically or diagonally. At the top of the lantern room is a stormproof ventilator designed to remove the smoke of the lamps and the heat that builds in the glass enclosure. A lightning rod and grounding system connected to

2680-492: The leader of a subsequent French expedition. The Point Matthew lookout on the road between Augusta and Cape Leeuwin has the islands identified in a brass compass plate that also identifies distances. There are a number of wrecks in the vicinity of Cape Leeuwin. The best-known wreck near the islands was that of the Aberdeen White Star ship SS Pericles on an uncharted rock on 13 March 1910, within sight of

2747-535: The light is concentrated, if needed, by the "lens" or "optic". Power sources for lighthouses in the 20th–21st centuries vary. Originally lit by open fires and later candles, the Argand hollow wick lamp and parabolic reflector were introduced in the late 18th century. Whale oil was also used with wicks as the source of light. Kerosene became popular in the 1870s and electricity and acetylene gas derived on-site from calcium carbide began replacing kerosene around

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2814-434: The light would appear to the mariners as a series of intermittent flashes. It also became possible to transmit complex signals using the light flashes. French physicist and engineer Augustin-Jean Fresnel developed the multi-part Fresnel lens for use in lighthouses. His design allowed for the construction of lenses of large aperture and short focal length , without the mass and volume of material that would be required by

2881-469: The lighthouse keepers. Efficiently concentrating the light from a large omnidirectional light source requires a very large diameter lens. This would require a very thick and heavy lens if a conventional lens were used. The Fresnel lens (pronounced / f r eɪ ˈ n ɛ l / ) focused 85% of a lamp's light versus the 20% focused with the parabolic reflectors of the time. Its design enabled construction of lenses of large size and short focal length without

2948-412: The mainland. This supposed isle is, therefore, what I denominate "Cape Leeuwin", as being the south-western and most projecting part of Leeuwin's Land.[3] The St Alouarn Islands is a group of islands off the tip of Cape Leeuwin. The lighthouse and adjacent buildings, and Cape Leeuwin water wheel are all within the historic precinct as reviewed by government management. The climate of Cape Leeuwin

3015-421: The metal cupola roof provides a safe conduit for any lightning strikes. Immediately beneath the lantern room is usually a Watch Room or Service Room where fuel and other supplies were kept and where the keeper prepared the lanterns for the night and often stood watch. The clockworks (for rotating the lenses) were also located there. On a lighthouse tower, an open platform called the gallery is often located outside

3082-509: The most brilliant light then known. The vaporized oil burner was invented in 1901 by Arthur Kitson , and improved by David Hood at Trinity House . The fuel was vaporized at high pressure and burned to heat the mantle, giving an output of over six times the luminosity of traditional oil lights. The use of gas as illuminant became widely available with the invention of the Dalén light by Swedish engineer Gustaf Dalén . He used Agamassan (Aga),

3149-763: The mouth of the Thames and was known as the Maplin Sands lighthouse, and first lit in 1841. Although its construction began later, the Wyre Light in Fleetwood, Lancashire, was the first to be lit (in 1840). Until 1782 the source of illumination had generally been wood pyres or burning coal. The Argand lamp , invented in 1782 by the Swiss scientist Aimé Argand revolutionized lighthouse illumination with its steady smokeless flame. Early models used ground glass which

3216-555: The next headland north, Cape Naturaliste , to identify the geography and ecology of the region. One example is in the name Leeuwin-Naturaliste National Park . Another is in the use of the phrases Cape to Cape or the Capes in tourist promotional materials. A shore base and a ship of the Royal Australian Navy have been named HMAS  Leeuwin after the cape. The Wardandi , an Aboriginal Australian people, were

3283-470: The providing of a visible warning against shipping hazards, such as rocks or reefs. The Eddystone Rocks were a major shipwreck hazard for mariners sailing through the English Channel . The first lighthouse built there was an octagonal wooden structure, anchored by 12 iron stanchions secured in the rock, and was built by Henry Winstanley from 1696 to 1698. His lighthouse was the first tower in

3350-451: The seabed and a low wooden structure is placed above the open framework, such as Thomas Point Shoal Lighthouse . As screw piles can be disrupted by ice, steel caisson lighthouses such as Orient Point Light are used in cold climates. Orient Long Beach Bar Light (Bug Light) is a blend of a screw pile light that was converted to a caisson light because of the threat of ice damage. Skeletal iron towers with screw-pile foundations were built on

3417-554: The siege of Atlanta, designed and built some of the most exotic lighthouses in the most difficult locations on the U.S. Great Lakes . French merchant navy officer Marius Michel Pasha built almost a hundred lighthouses along the coasts of the Ottoman Empire in a period of twenty years after the Crimean War (1853–1856). In a lighthouse, the source of light is called the "lamp" (whether electric or fuelled by oil) and

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3484-492: The standard for lighthouses for over a century. South Foreland Lighthouse was the first tower to successfully use an electric light in 1875. The lighthouse's carbon arc lamps were powered by a steam-driven magneto . John Richardson Wigham was the first to develop a system for gas illumination of lighthouses. His improved gas 'crocus' burner at the Baily Lighthouse near Dublin was 13 times more powerful than

3551-528: The surface during periods of fog or low clouds, as at Point Reyes Lighthouse . Another example is in San Diego , California : the Old Point Loma lighthouse was too high up and often obscured by fog, so it was replaced in 1891 with a lower lighthouse, New Point Loma lighthouse . As technology advanced, prefabricated skeletal iron or steel structures tended to be used for lighthouses constructed in

3618-599: The third and most famous Eddystone Lighthouse , but some builders are well known for their work in building multiple lighthouses. The Stevenson family ( Robert , Alan , David , Thomas , David Alan , and Charles ) made lighthouse building a three-generation profession in Scotland. Richard Henry Brunton designed and built 26 Japanese lighthouses in Meiji Era Japan, which became known as Brunton's "children". Blind Irishman Alexander Mitchell invented and built

3685-486: The traditional light, including in some cases a rotating beam. A typical LED system designed to fit into the traditional 19th century Fresnel lens enclosure was developed by Trinity House and two other lighthouse authorities and costs about € 20,000, depending on configuration, according to a supplier; it has large fins to dissipate heat. Lifetime of the LED light source is 50,000 to 100,000 hours, compared to about 1,000 hours for

3752-407: The turn of the 18th century, as the number of lighthouses being constructed increased significantly due to much higher levels of transatlantic commerce. Advances in structural engineering and new and efficient lighting equipment allowed for the creation of larger and more powerful lighthouses, including ones exposed to the sea. The function of lighthouses was gradually changed from indicating ports to

3819-480: The turn of the 20th century. Carbide was promoted by the Dalén light , which automatically lit the lamp at nightfall and extinguished it at dawn. In the second half of the 20th century, many remote lighthouses in Russia (then Soviet Union ) were powered by radioisotope thermoelectric generators (RTGs). These had the advantage of providing power day or night and did not need refuelling or maintenance. However, after

3886-463: The use of Fresnel lenses , and in rotation and shuttering systems providing lighthouses with individual signatures allowing them to be identified by seafarers. He also invented the movable jib and the balance-crane as a necessary part for lighthouse construction. Alexander Mitchell designed the first screw-pile lighthouse – his lighthouse was built on piles that were screwed into the sandy or muddy seabed. Construction of his design began in 1838 at

3953-535: The watch room (called the Main Gallery) or Lantern Room (Lantern Gallery). This was mainly used for cleaning the outside of the windows of the Lantern Room. Lighthouses near to each other that are similar in shape are often painted in a unique pattern so they can easily be recognized during daylight, a marking known as a daymark . The black and white barber pole spiral pattern of Cape Hatteras Lighthouse

4020-485: The waves to dissipate on impact with the walls. His lighthouse was the prototype for the modern lighthouse and influenced all subsequent engineers. One such influence was Robert Stevenson , himself a seminal figure in the development of lighthouse design and construction. His greatest achievement was the construction of the Bell Rock Lighthouse in 1810, one of the most impressive feats of engineering of

4087-643: The weight and volume of material in conventional lens designs. Fresnel lighthouse lenses are ranked by order , a measure of refracting power, with a first order lens being the largest, most powerful and expensive; and a sixth order lens being the smallest. The order is based on the focal length of the lens. A first order lens has the longest focal length, with the sixth being the shortest. Coastal lighthouses generally use first, second, or third order lenses, while harbor lights and beacons use fourth, fifth, or sixth order lenses. Some lighthouses, such as those at Cape Race , Newfoundland, and Makapuu Point , Hawaii, used

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4154-425: The world to have been fully exposed to the open sea. The civil engineer John Smeaton rebuilt the lighthouse from 1756 to 1759; his tower marked a major step forward in the design of lighthouses and remained in use until 1877. He modeled the shape of his lighthouse on that of an oak tree , using granite blocks. He rediscovered and used " hydraulic lime ", a form of concrete that will set under water used by

4221-417: The wreck to recover the lead that was being carried by the ship. Some shipwrecks are identified as being within the vicinity of Augusta, Cape Leeuwin or Hamelin Bay that might not be within visual distance of the lighthouse. Cape Leeuwin is mentioned in the poem associated with the children's story The Sing-Song of Old Man Kangaroo by Rudyard Kipling . The poem is also the best way for outsiders to learn

4288-437: Was a kerosene lamp or, earlier, an animal or vegetable oil Argand lamp, and the lenses rotated by a weight driven clockwork assembly wound by lighthouse keepers, sometimes as often as every two hours. The lens assembly sometimes floated in liquid mercury to reduce friction. In more modern lighthouses, electric lights and motor drives were used, generally powered by diesel electric generators. These also supplied electricity for

4355-426: Was aware that the area had been known to the Dutch as "Leeuwin's Land". At two in the morning we had 80 fathoms and veered towards the land. It was seen from the masthead at five; and the highest part, the same which had been set in the evening, bore N. 12° W. This is the largest of the before-mentioned Isles of St Alouarn; but at half past seven we saw hills extending from behind, and, to all appearance, joining it to

4422-407: Was sometimes tinted around the wick. Later models used a mantle of thorium dioxide suspended over the flame, creating a bright, steady light. The Argand lamp used whale oil , colza , olive oil or other vegetable oil as fuel, supplied by a gravity feed from a reservoir mounted above the burner. The lamp was first produced by Matthew Boulton , in partnership with Argand, in 1784, and became

4489-558: Was the Pharos of Alexandria , Egypt , which collapsed following a series of earthquakes between 956 and 1323. The intact Tower of Hercules at A Coruña , Spain gives insight into ancient lighthouse construction; other evidence about lighthouses exists in depictions on coins and mosaics, of which many represent the lighthouse at Ostia . Coins from Alexandria, Ostia, and Laodicea in Syria also exist. The modern era of lighthouses began at

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