British Indian Ocean Territory — De Facto Map

British Indian Ocean Territory — British Indian Ocean Territory · BOT · in transition · the United Kingdom.

Interactive de facto map of British Indian Ocean Territory, a territory of the United Kingdom. The Chagos Archipelago. Under the May 2025 UK–Mauritius treaty, sovereignty passes to Mauritius and the UK–US base on Diego Garcia is leased back for 99 years; the implementing Act passed Parliament in 2026. No civilian population since the Chagossians were removed between 1965 and 1973. Explore British Indian Ocean Territory on the map alongside the other overseas holdings of the United Kingdom, drawn as they are administered on the ground.