Mafia Island

Mafia sits south of Zanzibar and receives a fraction of its visitors, which is precisely its appeal. Chole Bay, sheltered by a chain of reefs and islets, is one of the finest protected bays in the region and the heart of Mafia Island Marine Park, with coral gardens, mangrove channels and turtle nesting beaches. The island's distinguishing feature is its whale sharks, which gather in the plankton-rich water off Kilindoni from roughly October to March and are unusual in that many individuals stay for months rather than passing through, so encounters are snorkelled from small boats rather than chased across open sea. Nearby Chole island holds the coral-stone ruins of a nineteenth-century settlement being swallowed by baobab and fig.

What you actually see

• Whale shark snorkelling - seasonal encounters off Kilindoni, from small boats.
• Chole Bay diving - sheltered coral gardens inside the reef barrier.
• Chole island ruins - overgrown coral-stone buildings and a boatbuilding village.
• Turtle nesting on Juani - green turtles laying on protected beaches in season.

When to go

October to March for whale sharks, with the peak usually around November to February. Diving visibility is best from about June to October. The long rains in April and May close much of the island's tourism.

Honest expectations

Getting there means flying, and flights are small and weather-dependent. Facilities are limited and the island is genuinely quiet, which is either the point or a disappointment. Whale shark encounters are wild and not guaranteed, and it is worth choosing an operator that follows the code of conduct on distances and boat numbers rather than the one that promises the closest approach.

Nearby

Zanzibar and Dar es Salaam are the air connections; the Rufiji delta lies opposite on the mainland.