Prison Island

About Prison Island

Prison Island, known locally as Changuu, sits a short boat ride from Stone Town and takes its name from a colonial-era building constructed to hold prisoners, though it was never actually used for that purpose. Today the island is better known for its population of giant Aldabra tortoises, some of them over a century old, brought here from Seychelles and now roaming freely within a protected sanctuary.

What to Expect

Visitors can walk among the tortoises, feeding them under supervision, before exploring the island's small beaches and snorkeling the surrounding reef. It is a popular half-day trip from Stone Town, easily combined with the city's historical sites earlier or later in the day.

Best Time to Visit

Prison Island can be visited year-round, though the dry seasons from June to October and December to February offer the calmest crossing and best snorkeling visibility.

Getting to Prison Island

The island is reached by a short boat trip directly from Stone Town's waterfront, making it one of the easiest half-day excursions available from the city.

Combine With: Prison Island is almost always paired with a Stone Town city tour, either as a morning excursion before an afternoon of walking the old town, or the reverse, making efficient use of a single day.

The tortoises here are remarkably long-lived, with several individuals documented as being well over a hundred years old, and the sanctuary's open enclosure allows visitors to get closer to them than most wildlife encounters permit. The island's small beach and clear water also make it a pleasant spot to relax between the tortoise visit and the boat back.

A short walk around the island's perimeter takes in ruins of the original quarantine station buildings, adding a small dose of history to what is otherwise primarily a wildlife and beach stop.