British Indian Ocean Territory

Landscape

The Chagos Archipelago consists of low coral islands and atolls in the central Indian Ocean. An atoll is a reef structure that surrounds a lagoon, often with small islands along its rim. Land occupies only a small part of the much wider reef-and-lagoon system.

Diego Garcia is the largest island in the archipelago and curves around a substantial lagoon. Other atolls contain scattered, smaller islands. These islands are widely separated, so a view of one lagoon cannot represent the full geographic extent of the territory.

Marine environment

Coral reefs, lagoons and open ocean are central to the archipelago’s ecology. Low elevation makes the boundary between land and sea particularly important. This geographic description does not resolve the archipelago’s sovereignty questions or the history of Chagossian displacement.