Ascension Island is an isolated volcanic island, 7°56′ south of the Equator in the South Atlantic Ocean. It is about 1,000 miles (1,600 km) from the coast of Africa and 1,400 miles (2,300 km) from the coast of South America. It is governed as part of the British Overseas Territory of Saint Helena, Ascension and Tristan da Cunha, of which the main island, Saint Helena, is around 800 miles (1,300 km) to the southeast. The territory also includes the sparsely populated Tristan da Cunha archipelago, 2,300 miles (3,700 km) to the south, about halfway to the Antarctic Circle.