In the South Atlantic Ocean, about half way between Africa and South America, are the British islands of Tristan da Cunha. Their nearest neighbour is St Helena, another British island 2,120km (1,317 miles) away. In 1961, a volcanic eruption forced the Tristan islanders to leave for Britain. But life in crowded Britain lacked appeal and most of them went home in 1963. The 300 or so islanders on Tristan da Cunha, a dependency of St Helena, are happy to live on the world’s most remote inhabited territory.