Prison Island, looking on the coast, gets its name from the prison built to condemn Zanzibar citizens to the isolation of the island. Previously owned by an Arab to house his rebellious slaves, the prison was never actually used, and the island is now home to a tortoise sanctuary and a hotel. Prison Island is 20 minutes away from Stone Town by boat, and has spectacular coral reefs for you to enjoy. Giant tortoises shuffle through the trees, with the infinite patience that old age brings. Originally thought to be from the Comoros Islands and Seychelles, some of these tortoises are thought to be over 100 years old. Stately and lumbering, the tortoises have even been known to take children on a ride.