Why a Tiny Island Created the Biggest Marine Sanctuary in the South Atlantic Tristan da Cunha was first inhabited to keep an eye on Napoleon; now residents are looking out for lobsters. Why a Tiny Island Created the Biggest Marine Sanctuary in the South Atlantic Copy Link The town center of Edinburgh of the Seven Seas, the island's only town. Dmitry Malov / Alamy Like most places, the British Overseas Territory of Tristan da Cunha is a community made up of teachers, accountants, mechanics, and grocers. But here, on the most remote inhabited island on earth, the weather has a funny way of rearranging the professional landscape.