Prison Island in short
Prison Island, called Changuu in Swahili, lies off Stone Town. Boats take 20 to 30 minutes each way in good conditions, so it fits into a half day. The island is known for its Aldabra giant tortoises, the old buildings, a sandy beach and a view back to the old town. Many boats also offer snorkelling.
The costs come in three parts: the boat, the island entry and the marine conservation fee. They are separate, and the prices below are for 2026 and can change.
Our picks: Prison Island tours
The boat trip with the sandbank suits you if you want to swim as well, the day trip with Stone Town and a spice farm fills a whole day, and the half-day is the shorter way to see the tortoises.
Hand-picked tours, booked through GetYourGuide and Viator. Prices are indicative starting prices in US dollars (as of October 2026). Tap a tour for live availability and the current price in your currency.
Stone Town and Prison Island half-day trip
- Hotel pick-up and drop-off
- Conservation fees
- Bottled water
A guide with an art-history background leads you through Stone Town and out to Prison Island. Ask whether island entry is included before you book.
Check availability →
Prison Island, Stone Town and a spice farm
- Boat to Prison Island
- Lunch
- Spice farm entry
A boat to Prison Island and a Stone Town visit with an English-speaking guide and lunch. Island entry and the slave market ticket only come with the options that include them.
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Prison Island and Nakupenda sandbank by boat with BBQ
- Boat both ways
- Snorkel gear and life jacket
- Soft drinks
Boat to both islands with a guide, a seafood BBQ and fruit. The marine conservation fee is paid on site and comes on top.
Check availability →Prison Island boat trips
Boat trips to Prison Island and combinations with a sandbank or snorkelling stop, with live prices and availability.
Prison Island fees: what you pay
Boat, entry and marine fee are different items.
| Visitor group | Marine conservation fee per day |
|---|---|
| Non-East Africans, 16 years and older | $10 |
| Non-East Africans, 5 to 15 years | $5 |
| Children under 5 | Free |
| Non-EAC residents of Tanzania, adult / child | $5 / $3 |
| East African citizens, adult / child | TZS 5,000 / TZS 2,500 |
Residency means status as a resident, not a hotel stay. The marine fee system moved to digital collection together with higher fees. On top of this comes the island entry, which costs about $4 to $12 depending on the trip, and the boat. Ask what the trip price includes and confirm the total before you pay.
For most visitors, the clearest way to book is a trip that includes the boat, the island entry and the marine fee in one price.
Prison Island tortoises
The animals most visitors come for.
The island is home to Aldabra giant tortoises. A story often told says that four animals came from the Seychelles in 1919. The number and the age of the tortoises vary from account to account, so do not rely on precise figures.
Treat the tortoises as animals, not props. Keep a calm distance, follow the guide's instructions, and do not feed them or climb on them.
Changuu Island: history
From planned prison to quarantine station.
The island was acquired in 1893 for a planned prison. The prison buildings were never used as a penal prison. The island served as a quarantine station instead. The old building with blue doors and windows is one of the things you see on the island.
The name Prison Island therefore describes a plan, not a long history of prisoners. For the wider story of the old town, read the history of Stone Town.
Snorkelling and the beach
Snorkelling is offered as an activity by tour operators. Visibility, currents and the animals you see depend on the day, and none of it can be guaranteed. The beach has shallow water.
Plan the rest of your trip
Where Prison Island fits.
Nakupenda sandbank
Often combined with Prison Island on the same day.
Stone Town tours
Walking tours, spice farms and boat trips compared.
Things to do in Stone Town
The sights on land.
For more islands and beaches around Unguja, see Mnemba Island and the east coast.
Prison Island: frequently asked questions
How do I get to Prison Island?
By boat from Stone Town. The ride takes 20 to 30 minutes each way in good conditions, depending on the boat, the departure point and the sea.
How much does Prison Island cost?
Boat, island entry and the marine conservation fee are separate. The marine fee is $10 per adult and day for non-East Africans. The island entry costs about $4 to $12 depending on the trip, so confirm the total.
Are there really giant tortoises?
Yes, Aldabra giant tortoises live on the island. Keep a distance and follow the guide.
Was Prison Island ever a prison?
It was acquired in 1893 for a planned prison, but it was not used as one. It became a quarantine station.
Can I swim or snorkel?
Snorkelling is offered on trips, and the beach has shallow water. Conditions change with the day, so ask your boat crew.
How long should I plan for Prison Island?
Boats take 20 to 30 minutes each way in good conditions, so the island fits into a half day.