An artificial island is an

island An island or isle is a piece of subcontinental land completely surrounded by water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island in a river or a lake island may be ...

that has been constructed by people rather than formed by natural means. Artificial islands may vary in size from small islets reclaimed solely to support a single pillar of a building or structure to those that support entire communities and cities. Early artificial islands included floating structures in still waters or

wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of ligni ...

en or

megalith A megalith is a large stone that has been used to construct a prehistoric structure or monument, either alone or together with other stones. There are over 35,000 in Europe alone, located widely from Sweden to the Mediterranean sea. The ...

ic structures erected in shallow waters (e.g. crannógs and Nan Madol discussed below). In modern times artificial islands are usually formed by

land reclamation Land reclamation, usually known as reclamation, and also known as land fill (not to be confused with a waste landfill), is the process of creating new land from oceans, seas, riverbeds or lake beds. The land reclaimed is known as reclam ...

, but some are formed by the incidental isolation of an existing piece of land during

canal Canals or artificial waterways are waterways or engineered channels built for drainage management (e.g. flood control and irrigation) or for conveyancing water transport vehicles (e.g. water taxi). They carry free, calm surface fl ...

construction (e.g. Donauinsel, Ko Kret, and much of

Door County, Wisconsin Door County is the easternmost Administrative divisions of Wisconsin#County, county in the U.S. state of Wisconsin. As of the 2020 United States Census, 2020 census, the population was 30,066. Its county seat is Sturgeon Bay, Wisconsin, Sturgeon ...

), or

flood A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrol ...

ing of valleys resulting in the tops of former knolls getting isolated by water (e.g., Barro Colorado Island). One of the world's largest artificial islands, René-Levasseur Island, was formed by the flooding of two adjacent reservoirs.

History

Despite a popular image of modernity, artificial islands actually have a long history in many parts of the world, dating back to the reclaimed islands of Ancient Egyptian civilization, the Stilt crannogs of prehistoric

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to th ...

and

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

, the ceremonial centers of Nan Madol in

Micronesia Micronesia (, ) is a subregion of Oceania, consisting of about 2,000 small islands in the western Pacific Ocean. It has a close shared cultural history with three other island regions: the Philippines to the west, Polynesia to the east, and ...

and the still extant floating islands of

Lake Titicaca Lake Titicaca (; es, Lago Titicaca ; qu, Titiqaqa Qucha) is a large freshwater lake in the Andes mountains on the border of Bolivia and Peru. It is often called the highest navigable lake in the world. By volume of water and by surface area ...

. The city of

Tenochtitlan , ; es, Tenochtitlan also known as Mexico-Tenochtitlan, ; es, México-Tenochtitlan was a large Mexican in what is now the historic center of Mexico City. The exact date of the founding of the city is unclear. The date 13 March 1325 was ...

, the

Aztec The Aztecs () were a Mesoamerican culture that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl ...

predecessor of

Mexico City Mexico City ( es, link=no, Ciudad de México, ; abbr.: CDMX; Nahuatl: ''Altepetl Mexico'') is the capital and largest city of Mexico, and the most populous city in North America. One of the world's alpha cities, it is located in the Valley of ...

that was home to 500,000 people when the Spaniards arrived, stood on a small natural island in

Lake Texcoco Lake Texcoco ( es, Lago de Texcoco) was a natural lake within the "Anahuac" or Valley of Mexico. Lake Texcoco is best known as where the Aztecs built the city of Tenochtitlan, which was located on an island within the lake. After the Spanish con ...

that was surrounded by countless artificial '' chinamitl'' islands. Malaita

The people of Langa Langa Lagoon and Lau Lagoon in Malaita, Solomon Islands, built about 60 artificial islands on the reef including Funaafou, Sulufou, and Adaege. The people of Lau Lagoon build islands on the reef as this provided protection against attack from the people who lived in the centre of Malaita. These islands were formed literally one rock at a time. A family would take their

canoe A canoe is a lightweight narrow water vessel, typically pointed at both ends and open on top, propelled by one or more seated or kneeling paddlers facing the direction of travel and using a single-bladed paddle. In British English, the term ...

out to the reef which protects the lagoon and then dive for rocks, bring them to the surface and then return to the selected site and drop the rocks into the water. Living on the reef was also healthier as the mosquitoes, which infested the coastal swamps, were not found on the reef islands. The Lau people continue to live on the reef islands. Many artificial islands have been built in urban

harbor A harbor (American English), harbour (British English; see spelling differences), or haven is a sheltered body of water where ships, boats, and barges can be docked. The term ''harbor'' is often used interchangeably with ''port'', which is a ...

s to provide either a site deliberately isolated from the city or just spare

real estate Real estate is property consisting of land and the buildings on it, along with its natural resources such as crops, minerals or water; immovable property of this nature; an interest vested in this (also) an item of real property, (more genera ...

otherwise unobtainable in a crowded metropolis. An example of the first case is

Dejima , in the 17th century also called Tsukishima ( 築島, "built island"), was an artificial island off Nagasaki, Japan that served as a trading post for the Portuguese (1570–1639) and subsequently the Dutch (1641–1854). For 220 years, ...

(or ''Deshima''), created in the bay of

Nagasaki is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan. It became the sole port used for trade with the Portuguese and Dutch during the 16th through 19th centuries. The Hidden Christian Sites in th ...

in Japan's

Edo period The or is the period between 1603 and 1867 in the history of Japan, when Japan was under the rule of the Tokugawa shogunate and the country's 300 regional ''daimyo''. Emerging from the chaos of the Sengoku period, the Edo period was character ...

as a contained center for

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

merchants A merchant is a person who trades in Commodity, commodities produced by other people, especially one who trades with foreign countries. Historically, a merchant is anyone who is involved in commerce, business or trade. Merchants have operated fo ...

. During the isolationist era, Dutch people were generally banned from Nagasaki and Japanese from Dejima. Similarly,

Ellis Island Ellis Island is a federally owned island in New York Harbor, situated within the U.S. states of New York and New Jersey, that was the busiest immigrant inspection and processing station in the United States. From 1892 to 1954, nearly 12 m ...

, in Upper New York Bay beside

New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the U ...

, a former tiny islet greatly expanded by

, served as an isolated

immigration Immigration is the international movement of people to a destination country of which they are not natives or where they do not possess citizenship in order to settle as permanent residents or naturalized citizens. Commuters, tourists, a ...

center for the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

in the late 19th and early 20th century, preventing an escape to the city of those refused entry for disease or other perceived flaws, who might otherwise be tempted toward

illegal immigration Illegal immigration is the migration of people into a country in violation of the immigration laws of that country or the continued residence without the legal right to live in that country. Illegal immigration tends to be financially upwar ...

. One of the most well-known artificial islands is the Île Notre-Dame in

Montreal Montreal ( ; officially Montréal, ) is the second-most populous city in Canada and most populous city in the Canadian province of Quebec. Founded in 1642 as '' Ville-Marie'', or "City of Mary", it is named after Mount Royal, the triple- ...

, built for Expo 67. The Venetian Islands in

Miami Beach, Florida Miami Beach is a coastal resort city in Miami-Dade County, Florida. It was incorporated on March 26, 1915. The municipality is located on natural and man-made barrier islands between the Atlantic Ocean and Biscayne Bay, the latter of which sep ...

, in

Biscayne Bay Biscayne Bay () is a lagoon with characteristics of an estuary located on the Atlantic coast of South Florida. The northern end of the lagoon is surrounded by the densely developed heart of the Miami metropolitan area while the southern end is la ...

added valuable new real estate during the Florida land boom of the 1920s. When the bubble that the developers were riding burst, the bay was left scarred with the remnants of their failed project. A boom town development company was building a sea wall for an island that was to be called Isola di Lolando but could not stay in business after the

1926 Miami Hurricane The Great Miami Hurricane of 1926 was a large and intense tropical cyclone that devastated the Greater Miami area and caused catastrophic damage in the Bahamas and the U.S. Gulf Coast in September of the year 1926, accruing a US$100 m ...

and the Great Depression, dooming the island-building project. The concrete pilings from the project still stand as another development boom roared around them, 80 years later.

Largest artificial islands according to their size (reclaimed lands)

Modern projects

Bahrain

Bahrain Bahrain ( ; ; ar, البحرين, al-Bahrayn, locally ), officially the Kingdom of Bahrain, ' is an island country in Western Asia. It is situated on the Persian Gulf, and comprises a small archipelago made up of 50 natural islands and an ...

has several artificial islands including Northern City,

Diyar Al Muharraq Diyar Al Muharraq () is a complex of seven artificial islands in the archipelago of Bahrain, located northeast of the capital, Manama, on Bahrain Island. History It's named after Muharraq Island, which is located near it. In December 2015 Drago ...

, and Durrat Al Bahrain. Named after the ‘most perfect pearl’ in the Persian Gulf, Durrat Al Bahrain is a US$ 6 billion joint development owned by the Bahrain Mumtalakat Holding Company and Kuwait Finance House Bahrain (KFH). The project is designed by the firm Atkins. It consists of a series of 15 large artificial islands covering an area of about 5 km2 (54,000,000 sq ft) and has six atolls, five fish-shaped islands, two crescent-shaped islands, and two more small islands related to the Marina area.

Netherlands

In 1969, the

Flevopolder The Flevopolder is an island polder forming the bulk of Flevoland, a province of the Netherlands. Created by land reclamation, its northeastern part was drained in 1955 and the remainder—the southwest—in 1968. Boundaries Unlike other major ...

in the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

was finished, as part of the Zuiderzee Works. It has a total land surface of 970 km², which makes it by far the largest artificial island by land reclamation in the world. The island consists of two polders, Eastern Flevoland and Southern Flevoland. Together with the Noordoostpolder, which includes some small former islands like Urk, the polders form

Flevoland Flevoland () is the twelfth and youngest province of the Netherlands, established in 1986, when the southern and eastern Flevopolders, together with the Noordoostpolder, were merged into one provincial entity. It is in the centre of the countr ...

, the 12th province of the Netherlands that almost entirely consists of reclaimed land. An entire artificial

archipelago An archipelago ( ), sometimes called an island group or island chain, is a chain, cluster, or collection of islands, or sometimes a sea containing a small number of scattered islands. Examples of archipelagos include: the Indonesian Archi ...

, Marker Wadden has been built as a conservation area for birds and other wildlife, the project started in 2016.

Maldives

Maldives The Maldives, officially the Republic of Maldives,, ) and historically known as the Maldive Islands, is a country and archipelagic state in South Asia in the Indian Ocean. The Maldives is southwest of Sri Lanka and India, about from the A ...

have been creating various artificial islands to promote

economic development In the economics study of the public sector, economic and social development is the process by which the economic well-being and quality of life of a nation, region, local community, or an individual are improved according to targeted goals a ...

and to address the threat of

rising sea level Globally, sea levels are rising due to human-caused climate change. Between 1901 and 2018, the globally averaged sea level rose by , or 1–2 mm per year on average.IPCC, 2019Summary for Policymakers InIPCC Special Report on the Ocean and Cry ...

. Hulhumalé island was reclaimed to establish a new land mass required to meet the existing and future housing, industrial and commercial development demands of the

Malé Malé (, ; dv, މާލެ) is the capital and most populous city of the Maldives. With a population of 252,768 and an area of , it is also one of the most densely populated cities in the world. The city is geographically located at the southern ...

region. The official settlement was inaugurated on May 12, 2004.

Qatar

The Pearl-Qatar is in the north of the Qatari capital

Doha Doha ( ar, الدوحة, ad-Dawḥa or ''ad-Dōḥa'') is the capital city and main financial hub of Qatar. Located on the Persian Gulf coast in the east of the country, north of Al Wakrah and south of Al Khor, it is home to most of the c ...

, home to a range of residential, commercial and tourism activities. Qanat Quartier is designed to be a 'Virtual

Venice Venice ( ; it, Venezia ; vec, Venesia or ) is a city in northeastern Italy and the capital of the Veneto region. It is built on a group of 118 small islands that are separated by canals and linked by over 400 bridges. The isla ...

in the Middle East'. Lusail & large areas around

Ras Laffan Ras Laffan Industrial City ( ar, راس لفان, Ra’s Lafān) is an industrial hub located north of Doha, Qatar. It is administrated by QatarEnergy. Ras Laffan Industrial City is Qatar's main site for production of liquefied natural gas ...

, Hamad International Airport & Hamad Port. The New Doha International Airport is the second largest artificial island built in the world, with a size of 22km2. The Pearl-Qatar is the third largest artificial island in the world, with a size of 13.9km2. The island was built in 2006, by main contractor DEME Group.

United Arab Emirates

The United Arab Emirates is home to several artificial island projects. They include the Yas Island, augmentions to

Saadiyat Island Saadiyat Island ( ar, جزيرة السعديات; ', for "Island of Happiness") is a natural island and a tourism-cultural project for nature and Emirati heritage and culture that is located in Abu Dhabi, United Arab Emirates. The project ...

, Khalifa Port, Al Reem Island, Al Lulu Island, Al Raha Creek, al Hudairiyat Island, The Universe and the Dubai Waterfront. Palm Islands ( Palm Jumeirah, Palm Jebel Ali, and Deira Island) and the World Islands off Dubai are created for leisure and tourism purposes. The Burj Al Arab is on its own artificial island. The Universe, Palm Jebel Ali, Dubai Waterfront, and Palm Deira are on hold.

China

China has conducted a land reclamation project which had built at least seven artificial islands in the

South China Sea The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by the shores of South China (hence the name), in the west by the Indochinese Peninsula, in the east by the islands of Taiwan and northwestern Phil ...

totaling 2000 acres in size by mid 2015. One artificial island built on Fiery Cross Reef near the Spratly Islands is now the site of a military

barracks Barracks are usually a group of long buildings built to house military personnel or laborers. The English word originates from the 17th century via French and Italian from an old Spanish word "barraca" ("soldier's tent"), but today barracks are ...

, lookout tower and a runway long enough to handle

Chinese military The People's Liberation Army (PLA) is the principal military force of the People's Republic of China and the armed wing of the Chinese Communist Party (CCP). The PLA consists of five service branches: the Ground Force, Navy, Air Force, ...

aircraft. A largely touristic and commercial project is the Ocean Flower Island project on Hainan island.

Airports

Kansai International Airport is the first airport to be built completely on an artificial island in 1994, followed by Chūbu Centrair International Airport in 2005, and both the

New Kitakyushu Airport , sometimes called Kokuraminami Airport, is an airport in Kokuraminami-ku, Kitakyushu, Fukuoka, Japan. It is built on an artificial island in the western Seto Inland Sea, away from the main body of the city. It opened on 16 March 2006, as but ...

and Kobe Airport in 2006, and

Ordu Giresun Airport Ordu () or Altınordu is a port city on the Black Sea coast of Turkey, historically also known as Cotyora or Kotyora ( pnt, Κοτύωρα), and the capital of Ordu Province with a population of 229,214 in the city center. Name Kotyora, the ori ...

in 2016. When

Hong Kong International Airport Hong Kong International Airport is Hong Kong's main airport, built on reclaimed land on the island of Chek Lap Kok, Hong Kong. The airport is also referred to as Chek Lap Kok International Airport or ''Chek Lap Kok Airport'', to distingu ...

opened in 1998, 75% of the property was created using

upon the existing islands of Chek Lap Kok and Lam Chau. Currently China is building several airports on artificial islands, they include runways of Shanghai international Airport

Dalian Jinzhouwan International Airport Dalian Jinzhouwan International Airport is an airport being built to serve the city of Dalian in Liaoning Province, northeast China. Once open it will replace the existing Dalian Zhoushuizi International Airport as the city's main airport. It ...

being built on a 21 square kilometer artificial island, Xiamen Xiang'an International Airport,

Sanya Hongtangwan International Airport Sanya Hongtangwan International Airport is an airport planned to be built to serve the city of Sanya in Hainan Province, China. It would be located on an artificial island in Hongtang Bay, about west of Sanya. Construction began in 2017, and th ...

Bentley Systems Bentley Systems, Incorporated is an American-based software development company that develops, manufactures, licenses, sells and supports computer software and services for the design, construction, and operation of infrastructure. The company's ...

which is being built on a 28 square kilometer artificial islands.

Environmental impact

Artificial islands negatively impact the marine environment. The large quantities of sand required to build these islands are acquired through

dredging Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing d ...

, which is harmful to

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. C ...

s and disrupts marine life. The increased amount of sand, sediment, and fine particles creates turbid conditions, blocking necessary UV rays from reaching coral reefs, creating coral turbidity (where more organic material is taken in by coral) and increasing bacterial activity (more harmful bacteria are introduced into coral). The construction of artificial islands also decreases the subaqueous area in surrounding waters, leading to habitat destruction or degradation for many species.

Political status

Under the

United Nations Convention on the Law of the Sea The United Nations Convention on the Law of the Sea (UNCLOS), also called the Law of the Sea Convention or the Law of the Sea Treaty, is an international agreement that establishes a legal framework for all marine and maritime activities. , 167 ...

treaty (UNCLOS), artificial islands are not considered harbor works (Article 11) and are under the jurisdiction of the nearest coastal state if within (Article 56). Artificial islands are not considered islands for purposes of having their own territorial waters or exclusive economic zones, and only the coastal state may authorize their construction (Article 60); however, on the

high seas The terms international waters or transboundary waters apply where any of the following types of bodies of water (or their drainage basins) transcend international boundaries: oceans, large marine ecosystems, enclosed or semi-enclosed region ...

beyond national jurisdiction, any "state" may construct artificial islands (Article 87). The unrecognised micronation known as the Principality of Sealand (often shorted to simply "Sealand") is entirely on a single artificial island.

Gallery

File:Kansai closeup.jpg, A view of Kansai International Airport from space File:Palm Island Resort.jpg, Palm Jumeirah in

Dubai Dubai (, ; ar, دبي, translit=Dubayy, , ) is the most populous city in the United Arab Emirates (UAE) and the capital of the Emirate of Dubai, the most populated of the 7 emirates of the United Arab Emirates.The Government and Politics ...

File:Palm jumeirah core.jpg, A closer view of the Palm Jumeirah File:Northstar Offshore Island Beaufort Sea.jpg, Northstar Island, an artificial island for oil drilling in the Beaufort Sea File:Sealand fortress.jpg, The Principality of Sealand's artificial island in the North Sea.

References

External links

Artificial Islands in The Law of the Sea
{{Authority control artificial * Coastal construction Land reclamation