Zanzibar Diving & Snorkelling: The Complete Guide

Zanzibar sits at the edge of some of the Indian Ocean's most biodiverse marine territory. The warm, clear waters surrounding the island are home to sea turtles, whale sharks, manta rays, dolphins, and hundreds of species of tropical fish. Whether you're a first-time snorkeller or an experienced diver, the underwater world here is extraordinary.

Best Snorkelling Sites

Mnemba Atoll

The crown jewel of Zanzibar's underwater world. Mnemba Atoll is a protected marine reserve off the north-east coast with some of the best coral and marine life in the Indian Ocean. Expect sea turtles, spinner dolphins, hawksbill turtles, eagle rays and an extraordinary variety of reef fish. Visibility is often 20–30 metres on calm days.

Prison Island (Changuu)

The coral reef surrounding Prison Island is shallow and perfect for beginner snorkellers. The water is calm, clear and teeming with colourful reef fish. Combine it with a visit to the giant tortoises on the island for a half-day that ticks multiple boxes.

Chumbe Island Coral Park

One of the most pristine coral ecosystems in East Africa. Chumbe Island is a private marine sanctuary with almost no boat traffic — the coral here is in extraordinary condition. Day trips are available but expensive ($100+ per person). Worth it for serious snorkellers.

Leven Bank

A deep-water site further offshore known for pelagic species — whale sharks, manta rays, and large schools of barracuda. Only accessible on full-day boat trips from Zanzibar Town or Nungwi.

Best Dive Sites

• ✦Mnemba Atoll — best overall, suitable for all levels, rich marine life
• ✦Leven Bank — advanced, pelagic species including whale sharks and manta rays
• ✦Fundu Lagoon Wall — dramatic wall dive in the Pemba Channel, advanced
• ✦Big Wall (Nungwi) — steep coral wall starting at 12m, excellent reef fish diversity
• ✦Aquarium (Nungwi) — shallow sheltered reef, perfect for beginners and Open Water training

Whale Shark Season

Whale sharks visit the waters around Zanzibar and nearby Mafia Island between October and February, with peak sightings in November and December. These gentle giants — the largest fish on Earth — can reach 12 metres but are completely harmless to swimmers. Swimming alongside one is a once-in-a-lifetime experience. Most tours depart from Mafia Island, a 45-minute flight from Zanzibar.

Sea Turtles

Green and hawksbill sea turtles are resident around Zanzibar's reefs year-round. The Mnarani Natural Aquarium in Nungwi is a tidal pool sanctuary that rehabilitates injured turtles — you can see them up close and snorkel with wild turtles on the reef nearby. Mnemba Atoll is the best place to encounter turtles in their natural habitat.

Learning to Dive in Zanzibar

Zanzibar is an excellent place to get PADI or SSI certified. The calm, warm, clear water makes it ideal for beginners, and course prices are competitive. A PADI Open Water course typically takes 3–4 days and costs $350–500 depending on the operator.

• ✦Discovery Dive (no experience needed, supervised): $60–80
• ✦PADI Open Water Course (full certification, 3–4 days): $350–500
• ✦PADI Advanced Open Water: $280–380
• ✦2-tank fun dive (certified divers): $70–100 including equipment

Best Time for Diving & Snorkelling

The best diving and snorkelling conditions are from June to October (long dry season) and December to February (short dry season). The clearest water and calmest seas are in August and September. Avoid diving during the heavy rain season (March–May) when visibility drops and seas can be rough.