Prison Island (Changuu)

Giant tortoises, coral reef and a quarantine station that was never a prison.

Changuu was used as a penitentiary for rebel slaves by the sultans from the 1860s until the end of the slave trade. The British then built a prison, completed in 1894, but it was only ever used as a quarantine centre for possible yellow fever cases. Today the island is home to giant land tortoises brought from Seychelles in the 19th century — some over a hundred years old — which you can feed and pet.

There is excellent snorkelling, and the forested interior holds birds, peacocks, bats, butterflies and the shy duiker.