Mafia lies south of Zanzibar and sees a small fraction of its visitors. Mafia Island Marine Park, gazetted in 1995, was the first marine protected area in Tanzania and covers a reef system that has escaped much of the damage seen elsewhere in the region.
The island’s best-known draw is whale sharks. Unlike most aggregation sites worldwide, Mafia’s are largely resident rather than migratory, and they feed in the shallow, plankton-rich water of Kilindoni Bay where snorkelling with them is straightforward. The season runs roughly October to March.
Diving on Chole Bay’s coral gardens is exceptional, with steep walls and very high fish diversity. Green turtles nest on Juani and Jibondo, and the ruins at Chole Mjini and Kua record the island’s Shirazi and Omani past.