Tristan da Cunha, colloquially Tristan, is both a remote group of volcanic islands in the south Atlantic Ocean and the main island of that group. It is the most remote inhabited archipelago in the world, lying 2,816 kilometres (1,750 mi) from the nearest land, South Africa, and 3,360 kilometres (2,088 mi) from South America. The territory consists of the main island of Tristan da Cunha itself, which has a north-south length of 11.27 kilometres (7.0 mi) and has an area of 98 square kilometres (37.8 sq mi), along with the smaller, uninhabited Nightingale Islands and the wildlife reserves of Inaccessible and Gough Islands.

Tristan da Cunha is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha This includes Saint Helena 2,430 kilometres (1,510 mi) to its north and equatorial Ascension Island some 3,730 kilometres (2,318 mi) to the north of Tristan. The island has a permanent population of 275 (2009 figures).