Ashmore and Cartier Islands

Updated August 11, 2026

Area

5.00 km²

CIA World Factbook archive

CIA World Factbook map of Ashmore and Cartier Islands, showing major cities, rivers and neighbouring countries — Map from The World Factbook, final edition. Public domain (17 U.S.C. § 105); boundary representation is not necessarily authoritative.

Region: Australia and Oceania
Area: 5.00 km²

The Factbook archive 28 fields · 6 categories

The complete World Factbook entry for Ashmore and Cartier Islands: 28 fields and 17 sub-entries across 6 categories, kept whole as historical reference. A United States Government work in the public domain, reflecting data as of the final January 2026 edition. Last CIA update: January 5, 2026.

Introduction 1 field

Background: Indonesian fishermen have long fished in the area around Ashmore Reef and Cartier Island. British explorers were the first Europeans to see Cartier Island and Ashmore Reef in 1800 and 1811, respectively. American whalers frequently sailed by the islands in the 1850s and later settled to mine the phosphate deposits on Ashmore Reef, which were exhausted by 1891. The UK disputed US access to Ashmore Reef and formally annexed it in 1878. Cartier Island was annexed in 1909. In 1931, the UK transferred the islands to Australia, which accepted them in 1934 as part of Western Australia. In 1938, Australia transferred governance to the Northern Territory. During World War II, Cartier Island was used as a bombing range. In 1978, governance of Ashmore and Cartier Islands was moved to the federal government. Ashmore Reef and Cartier Island became marine reserves in 1983 and 2000 respectively.

In 1974, Australia and Indonesia signed a memorandum of understanding (MOU) to allow Indonesian fishermen to continue fishing around the islands. The MOU also allows Indonesian fishermen to visit the graves of past fishermen, replenish their fresh water, and shelter in the West Island Lagoon of Ashmore Reef. In the 1990s, Indonesia challenged Australia’s claim to the islands, which was settled in a maritime boundary treaty in 1997. The islands were a popular first point of contact for migrants and refugees seeking to enter Australia, so in 2001, Australia declared the islands to be outside the Australian migration zone.

Geography 15 fields

Location: Southeastern Asia, islands in the Indian Ocean, midway between northwestern Australia and Timor island; Ashmore Reef is 840 km west of Darwin and 610 km north of Broome; Cartier Islet is 70 km east of Ashmore Reef
Geographic coordinates: 12 25 S, 123 20 E

note: Ashmore Reef - 12 14 S, 123 05 E; Cartier Islet - 12 32 S, 123 32 E
Map references: Southeast Asia
Area: total: 5 sq km
land: 5 sq km
water: 0 sq km
Area - comparative: about eight times the size of the National Mall in Washington, D.C.
Land boundaries: total: 0 km
Coastline: 74.1 km
Maritime claims: territorial sea: 12 nm
contiguous zone: 24 nm
continental shelf: 200-m depth or to the depth of exploitation
exclusive fishing zone: 200 nm
Climate: tropical
Terrain: low with sand and coral
Elevation: highest point: Cartier Island 5 m
lowest point: Indian Ocean 0 m
Natural resources: fish
Land use: agricultural land: 0% (2018 est.)
Natural hazards: surrounded by shoals and reefs that can pose maritime hazards
Geography - note: Ashmore Reef National Nature Reserve established in 1983; Cartier Island Marine Reserve established in 2000

People and Society 1 field

Population: total: no permanent inhabitants

Environment 3 fields

Environmental issues: illegal killing of protected wildlife; overfishing; sea-level rise, changes in sea temperature, and ocean acidification; marine debris
Climate: tropical
Land use: agricultural land: 0% (2018 est.)

Government 7 fields

Country name: conventional long form: Territory of Ashmore and Cartier Islands
conventional short form: Ashmore and Cartier Islands
etymology: named after British Captain Samuel ASHMORE, who first sighted the island in 1811, and after the ship Cartier, from which the second island was discovered in 1800
Dependency status: territory of Australia; administered from Canberra by the Department of Regional Australia, Local Government, Arts and Sport
Legal system: the laws of the Commonwealth of Australia and the laws of the Northern Territory of Australia, where applicable, apply
Citizenship: see Australia
Diplomatic representation in the US: none (territory of Australia)
Diplomatic representation from the US: embassy: none (territory of Australia)
Flag: the flag of Australia is used

Military and Security 1 field

Military - note: defense is the responsibility of Australia

Location