A quiet island off the Rufiji delta with Tanzania's oldest multi-user marine park and a resident population of whale sharks
Mafia Island lies in the Indian Ocean opposite the delta of the Rufiji River, separated from the mainland by a channel about 20 kilometres wide. Unlike Zanzibar, it has seen little large-scale tourism: there is one main town, Kilindoni, a scattering of villages and a handful of small lodges. Life moves at the pace of the tides and the fishing boats.
Under the water, Mafia is one of East Africa's richest marine areas. Coral reefs, seagrass beds and mangrove channels shelter abundant reef fish, and the island is known for a resident population of whale sharks, most often seen between October and March, when visitors can snorkel alongside them. Diving in Chole Bay and on the outer reefs, island hopping and visits to historic ruins round out a stay.
Mafia has been part of the Indian Ocean trading world for well over a thousand years. Settlements such as Chole Mjini, on a small island in Chole Bay, were linked to the gold and ivory trade that passed through Kilwa further south. On neighbouring Juani Island stand the ruins of Kua, a town attacked in the 1820s by Sakalava raiders from Madagascar, who killed or enslaved many of its people.
In 1890 Germany acquired Mafia, together with the mainland coast, from the Sultan of Zanzibar, and German-era buildings still stand on Chole. British forces took the island in 1915, during the First World War. In 1995 Mafia Island Marine Park was created, Tanzania's first multi-user marine park, where fishing and other local uses continue under park rules. It covers some 822 square kilometres of sea, reef and islands, and studies have found larger fish inside its boundaries than outside, although restrictions on fishing grounds have also caused hardship for some villagers.
Over 65,000 people live on Mafia, mostly in fishing and farming villages, and the market in Kilindoni is the island's commercial centre. Fishing, small-scale farming and tourism support most families, and whale shark tourism has become one of the community's key sources of income, giving local people a direct stake in protecting the sharks.
Most visitors stay at one of the small lodges on the island, several of which are listed by the marine park authority, and tourist boats leave from Utende. Dive centres run trips to sites in Chole Bay and on the outer reefs, depending on tides and season, and dhows take snorkellers to sandbanks and coral gardens. Whale shark excursions run during the season, with small boats spotting the sharks as they feed near the surface.
On land, a boat trip across to Chole and Juani islands takes in mangroves, old stone ruins and village life. Because the island is quiet and accommodation limited, it pairs well with a busier stay on Zanzibar or a safari in Nyerere National Park across the channel.
The peak whale shark season runs from October to March, which is also a popular time for diving. The long rains, mainly from March to May, bring heavy showers and rougher crossings. Conditions on the more exposed outer reefs depend on wind and tide, so dive centres choose sites day by day.
Checked against the sources on 28 October 2026. Opening times and fees can change — confirm before you go.
General guidance from our specialists, not official information.
Chole, Juani and Jibondo islands lie in and around Chole Bay, and the Rufiji delta and Nyerere National Park are across the channel on the mainland. Dar es Salaam is a short flight away, and Kilwa Kisiwani lies further south along the coast.
Tanzania · 10 nights5★ LodgeTanzania · 8 nights5★ LodgeTanzania · 5 nights5★ LodgeThis guide was researched from the sources below and reviewed by our team on 28 October 2026. Facts under “Verified information” link to the page they were checked on; travel tips are general guidance. Photos are credited on each image. The ambient recording’s author and licence are shown in the sound player.
