Which archipelago is Inaccessible Island part of?

Inaccessible Island is an extinct volcano, last active six million years ago, with Cairn Peak reaching 449 m (1,473 ft). The island is 12.65 km2 (4.88 sq mi) in area, rising out of the South Atlantic Ocean 31 km (19 mi) south-west of Tristan da Cunha.

Inaccessible Island is part of the archipelago of Tristan da Cunha, which is part of the overseas territory of the United Kingdom known as Saint Helena, Ascension and Tristan da Cunha.

Inaccessible Island is fringed with sheer sea cliffs, with only one narrow, short, pebbly beach on its north face. Generations of sailors were wary of the difficult landing and inhospitable terrain. It has been without permanent inhabitants since 1873.

The island is home to dozens of plant species, but very few animals. Despite the lack of fauna, it is home to the endemic Inaccessible Island rail, the world's smallest extant flightless bird.