Prison Island’s Giant Tortoises: What to Know Before You Go

No — Prison Island was never actually used as a prison. The building went up in 1893 and ended up as a quarantine station instead, and today the island is known for one thing above all: giant tortoises that have been here for longer than almost anyone visiting them has been alive. It’s a short boat ride from Stone Town, it suits young kids better than most day trips on this list, and a private visit runs from $60 per person once there are six of you.

The prison that was never a prison

The name sticks because it’s a good story, but it’s slightly the wrong one. The building on the island was constructed in 1893, intended as a prison for people who had defied the Sultan of Zanzibar. It was never used for that purpose. Instead it became a quarantine station — a place to hold people arriving with yellow fever and other infectious diseases before they were allowed onto the main island. The colonial-era buildings are still there, and the guide who takes you round will point out which room was which. It’s a five-minute story, not a full history lesson, and it’s the kind of detail that makes the tortoises land better once you know it.

The Aldabra giant tortoises

The tortoises are the actual reason to go. They were a gift from the Seychelles government in the 1900s, part of the same conservation effort that protects Aldabra giant tortoises on their home atoll, and they have been breeding on the island ever since. Walk into the enclosure and they come towards you rather than away — they’re used to people, and you’re allowed to get close and touch their shells gently, though not to pick them up or feed them anything except what the keepers hand out. The oldest tortoise on the island is over 190 years old, which means it was alive before Zanzibar had electricity, before the sultanate ended, before almost anything currently standing on the island was built. Guides usually know which one it is and will point it out if you ask.

What a visit actually looks like

You’re picked up from your hotel and driven to the departure point, then it’s a short boat crossing — much shorter than the ride out to Safari Blue or Mnemba — to the island itself. Once there, the standard order is the tortoise enclosure first, then time to look around the old quarantine buildings and walk the island’s edge, where the water is clear enough that people often go in for a swim even without booking it as a snorkelling stop specifically. There’s shade throughout, which matters if you’re travelling with small children or anyone who doesn’t want a full day in direct sun, and it’s genuinely one of the shorter day trips on the island rather than an all-day commitment.

Price by group size

Like most of our boat trips, the per-person price drops sharply as the group gets bigger, because the boat and guide cost is fixed regardless of how many people are on board:

• 1 person: $200
• 2 people: $100 per person
• 3 people: $90 per person
• 4 to 5 people: $70 per person
• 6 or more: $60 per person

This is our Prison Island tour, and it’s private rather than a shared departure, so those prices are for your group alone, not split with strangers.

What’s included, and what isn’t

The price covers the boat, your guide, entry fees to the tortoise sanctuary, hotel pick-up and drop-off, drinking water, and the marine park fee. Lunch is the one thing not included — most guests either eat before they leave or after they’re back, since the trip is short enough that going hungry for a few hours isn’t really an issue.

Why it’s the easiest half-day for families

Of everything we run, this is the one we’d point a family with young kids towards first. The boat crossing is short enough that seasickness and boredom rarely become a problem, there’s shade to retreat to if a child has had enough sun, and giant tortoises are simply easier for a five-year-old to engage with than a snorkelling mask or a sailing dhow. The history angle helps too — “look, a tortoise” gets a child’s attention for about ninety seconds, but “this tortoise is older than your great-great-grandparents” tends to land a bit better, and it’s true rather than embellished for effect.

Pair it with another half-day

Because the trip itself only takes up part of a day, a lot of guests combine it with something else rather than treating it as a standalone booking. Jozani Forest, home to the Zanzibar red colobus monkey and found nowhere else on Zanzibar’s day-trip circuit, sits on roughly the same side of the island and works well as a second stop on the same day if you’d rather see two things than spend the whole day on one. If you’d prefer to stay on the water, Prison Island also combines naturally with Nakupenda Sandbank for a fuller day out at sea. Our guide to saving money on tours covers why combining two shorter trips in one day is usually cheaper than booking them separately — the transfers overlap, so you’re not paying for two full days of logistics.

Common questions before you book

Can you swim at Prison Island?

Yes, informally. The water around the jetty and along the island’s edge is clear and shallow enough that most guests go in for a while after the tortoise enclosure, even though this isn’t billed as a snorkelling trip. Bring a swimsuit under your clothes and you won’t need to plan around it separately.

Is it suitable for elderly relatives or anyone with limited mobility?

Better than most of our boat trips. The crossing is short, the tortoise enclosure is flat and easy to walk around, and there’s shade near the old buildings if someone needs to sit out part of the visit. It’s one of the few full day trips we’d comfortably recommend for a mixed group spanning grandparents to toddlers.

Do you need to book ahead?

A few days’ notice is sensible in July to September, when demand across all our boat trips is highest, but Prison Island is generally easier to arrange on short notice than Safari Blue or Mnemba, since it isn’t tide-dependent in the way a sandbank trip is.

When to go

Unlike Nakupenda or the mangrove trips, Prison Island doesn’t move with the tide, so there’s no single best departure time dictated by the sea. Mornings tend to be quieter and cooler, which matters more here than on some trips because there’s real walking involved between the enclosure and the old buildings. If you’re combining it with Jozani Forest or Nakupenda on the same day, we’ll usually suggest Prison Island first, since it’s the shorter of the two halves and gives you a buffer if the second stop runs late.

Key facts

• The building was constructed in 1893 as a prison but was used as a quarantine station instead — it was never used to hold prisoners.
• The Aldabra giant tortoises were a gift from the Seychelles, and the oldest resident tortoise is over 190 years old.
• Private trips run from $60 per person at six people up to $200 for a solo visit.
• The trip is around 5 hours door to door, shorter than most of our full-day boat trips.

How we can help

Prison Island is one of the more straightforward bookings we run, but the question we get most is what to pair it with, because on its own it doesn’t fill a whole day. Tell me who’s travelling and whether you’d rather stay on the water or head inland for the second half of the day, and I’ll suggest a combination that actually works with your dates rather than just selling you the longest itinerary.

Message me on WhatsApp with your group size and I’ll confirm availability and the exact price for your dates.