Artificial island
An artificial island or man-made island is an island that has been constructed by humans rather than formed through natural processes. Other definitions may suggest that artificial islands are lands with the characteristics of human intervention in their formation process, while others argue that artificial islands are created by expanding existing islets, constructing on existing reefs, or amalgamating several islets together. Although constructing artificial islands is not a modern phenomenon, there is no definite legal definition of it. 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. Archaeologists argue that such islands were created as far back as the Neolithic era. Early artificial islands included floating structures in still waters or wooden or megalithic structures erected in shallow waters.
In modern times, artificial islands are usually formed by land reclamation, but some are formed by flooding of valleys resulting in the tops of former knolls getting isolated by water. There are several reasons for the construction of these islands, which include residential, industrial, commercial, structural or strategic purposes. One of the world's largest artificial islands, René-Levasseur Island, was formed by the flooding of two adjacent reservoirs. Technological advancements have made it feasible to build artificial islands in waters as deep as 75 meters. The size of the waves and the structural integrity of the island play a crucial role in determining the maximum depth.
History
Despite a popular image of modernity, artificial islands actually have a long history in many parts of the world, dating back to Al-Sayah Island, in Bahrain – the world's first permanent artificial island, created at least 1,200 years ago around a water spring. Ancient reclaimed islands of Ancient Egyptian civilization, the Stilt crannogs of prehistoric Wales, Scotland and Ireland, the ceremonial centers of Nan Madol in Micronesia and the still extant floating islands of Lake Titicaca can also be found. Made around The city of Tenochtitlan, the Aztec predecessor of Mexico City that was home to 500,000 people when the Spaniards arrived, stood on a small natural island in Lake Texcoco that was surrounded by countless artificial chinamitl islands.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 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 harbors to provide either a site deliberately isolated from the city or just spare real estate otherwise unobtainable in a crowded metropolis. An example of the first case is Dejima, created in the bay of Nagasaki in Japan's Edo period as a contained center for European merchants. During the isolationist era, Dutch people were generally banned from Nagasaki and Japanese from Dejima. Similarly, Ellis Island, in Upper New York Bay beside New York City, a former tiny islet greatly expanded by land reclamation, served as an isolated immigration center for the United States 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. One of the most well-known artificial islands is the Île Notre-Dame in Montreal, built for Expo 67.
The Venetian Islands in Miami Beach, Florida, in Biscayne Bay 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 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)
| No. | Name | Size | Location | Year built | Utilisation |
| 1 | Flevopolder | 970 | Flevoland, Netherlands | 1955 & 1968 | Towns, agriculture |
| 2 | Hong Kong International Airport | Hong Kong | 1998, 2017 & 2022 | Airport, border control point | |
| 3 | The Pearl Island | Doha, Qatar | 2006 | Housing | |
| 4 | Diyar Al Muharraq | Muharraq, Bahrain | 2013 | Town | |
| 5 | Kansai International Airport | 10.68 | Osaka, Japan | 1994 | Airport |
| 6 | 10.54 | Osaka, Japan | 1970s | Town | |
| 7 | Port Island | Kobe, Japan | 1980 & 2009 | Housing | |
| 8 | Chūbu Centrair International Airport | Tokoname, Japan | 2005 | Airport | |
| 9 | Ogizima | Yokohama, Japan | 1975 | Factory | |
| 10 | Rokko Island | Kobe, Japan | 1992 | Housing | |
| 11 | Fundão Island | Rio de Janeiro, Brazil | 1983 | Federal University of Rio de Janeiro |
Modern projects
Bahrain
has several artificial islands including Northern City, Diyar Al Muharraq, 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. 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 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 in the Netherlands 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, the 12th province of the Netherlands that almost entirely consists of reclaimed land.An entire artificial archipelago, Marker Wadden has been built as a conservation area for birds and other wildlife, the project started in 2016.
Maldives
have been creating various artificial islands to promote economic development and to address the threat of rising sea level. 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 region. The official settlement was inaugurated on May 12, 2004.Qatar
is in the north of the Qatari capital Doha, home to a range of residential, commercial and tourism activities. Qanat Quartier is designed to be a 'Virtual Venice in the Middle East'. Lusail & large areas around Ras Laffan, 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, augmentations to Saadiyat Island, Khalifa Port, Al Reem Island, Al Lulu Island, Al Raha Creek, al Hudairiyat Island, The Universe and the Dubai Waterfront. Palm Islands 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
For decades, the Philippines and Vietnam were the most active in building artificial islands in the Spratly Islands, but from 2014 to 2016 China's construction activity outpaced them, constructing at least seven islands. By 2023, China had reclaimed around five square miles. One artificial island built on Fiery Cross Reef houses military barracks and a runway long enough to handle Chinese military aircraft.Background
The Spratly Islands are claimed by China, Taiwan, and Vietnam. Brunei, Malaysia, and the Philippines also claim some of the features in the island chain. By the 1970s, the Philippines, Taiwan, and Vietnam had militarily occupied one or more of the islands. By 2015, the PRC had established 8 outposts, Malaysia 5, the Philippines 8, Taiwan 1, on the largest Taiping Island, and Vietnam 48, by far the most numerous.China's claim to the area dates back to at least the 1940s. It began building islands in the 1980s in the form of minor military garrisons. Some of its reclamation projects fall within the EEZs of other countries, which led to criticism and concerns about China's compliance with UNCLOS.