British Indian Ocean Territory

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Established as a territory of the UK in 1965, a number of the British Indian Ocean Territory (BIOT) islands were transferred to the Seychelles when it attained independence in 1976. Subsequently, BIOT has consisted only of the six main island groups comprising the Chagos Archipelago. The largest and most southerly of the islands, Diego Garcia, contains a joint UK-US naval support facility. All of the remaining islands are uninhabited. Former agricultural workers, earlier residents in the islands, were relocated primarily to Mauritius but also to the Seychelles, between 1967 and 1973. In 2000, a British High Court ruling invalidated the local immigration order that had excluded them from the archipelago, but upheld the special military status of Diego Garcia.


archipelago in the Indian Ocean, south of India, about one-half the way from Africa to Indonesia

Geographic coordinates:

6 00 S, 71 30 E


total: 60 sq km
note: includes the entire Chagos Archipelago
water: 0 sq km
land: 60 sq km

Land boundaries:

0 km


698 km


tropical marine; hot, humid, moderated by trade winds


flat and low (most areas do not exceed four meters in elevation)

Elevation extremes:

lowest point: Indian Ocean 0 m
highest point: unnamed location on Diego Garcia 15 m

Natural resources:

coconuts, fish, sugarcane

Geography - note:

archipelago of 2,300 islands; Diego Garcia, largest and southernmost island, occupies strategic location in central Indian Ocean; island is site of joint US-UK military facility


no indigenous inhabitants
note: approximately 1,200 former agricultural workers resident in the Chagos Archipelago, often referred to as Chagossians or Ilois, were relocated to Mauritius and the Seychelles in the 1960s and 1970s, in November 2000 they were granted the right of return by a British High Court ruling, though no timetable has been set; in 2001, there were approximately 1,500 UK and US military personnel and 2,000 civilian contractors living on the island of Diego Garcia (July 2004 est.)

Dependency status:

overseas territory of the UK; administered by a commissioner, resident in the Foreign and Commonwealth Office in London

Legal system:

the laws of the UK, where applicable, apply

Economy - overview:

All economic activity is concentrated on the largest island of Diego Garcia, where joint UK-US defense facilities are located. Construction projects and various services needed to support the military installations are done by military and contract employees from the UK, Mauritius, the Philippines, and the US. There are no industrial or agricultural activities on the islands. When the Ilois return, they plan to reestablish sugarcane production and fishing.

Telephone system:

general assessment: separate facilities for military and public needs are available
domestic: all commercial telephone services are available, including connection to the Internet
international: international telephone service is carried by satellite (2000)

Internet Service Providers (ISPs):

1 (2000)


total: NA km
paved: short section of paved road between port and airfield on Diego Garcia
unpaved: NA km

Ports and harbors:

Diego Garcia


1 (2003 est.)

Airports - with paved runways:

total: 1
over 3,047 m: 1 (2003 est.)

Military - note:

defense is the responsibility of the UK; the US lease on Diego Garcia expires in 2016

Disputes - international

Mauritius and Seychelles claim the Chagos Archipelago and its former inhabitants, who reside chiefly in Mauritius, but in 2001 were granted UK citizenship and the right to repatriation since eviction in 1965; the UK resists the Chagossians' demand for an immediate return to the islands; repatriation is complicated by the exclusive US military lease of Diego Garcia that restricted access to the largest island in the chain