Mafia Island — known in Swahili as Chole Shamba, meaning 'Chole farmlands' — is the largest island of the Mafia Archipelago, sitting roughly 200 km south of Zanzibar in Tanzania's southern Pwani Region. According to Wikipedia, the island is the third largest in Tanzanian ocean territory and is home to a population of over 65,000 people, yet remains remarkably unhurried: Gates notes on camera that it is 'about six times the size of Manhattan' but has only around 3% of Manhattan's population. Visitors today find a landscape shaped by fishing villages, subsistence agriculture, and a modest tourist economy that draws scuba divers, birdwatchers, and game fishermen rather than mass tourism. The island sits at approximately seven degrees south latitude — a detail that becomes critical to the archaeological mystery Gates traveled here to investigate. That coordinate places Mafia Island in precise alignment with the ancient geographer Ptolemy's recorded location for Rhapta, a lost East African trading city sometimes called 'Africa's Atlantis,' making it the primary focus of an ongoing archaeological search that Gates joined for the Expedition Unknown episode 'Chasing Africa's Atlantis.'
Greco-Roman geographer Ptolemy records a trading city called Rhapta at approximately seven degrees south latitude along the East African coast, believed by some researchers to correspond to the Mafia Island region
Indian Ocean trade networks expand significantly along the Swahili Coast, with islands like Mafia serving as key waypoints for Arab, Persian, and Indian merchants
Mafia Island is administratively separated from Zanzibar's political territory, a distinction that persists today
Josh Gates travels to Mafia Island for Expedition Unknown S13E05 'Chasing Africa's Atlantis,' joining two separate archaeology teams searching for the lost city of Rhapta
The search for Rhapta — the lost emporium described by Ptolemy in his 1st-to-2nd-century AD geographical writings — is a genuine and ongoing pursuit within mainstream archaeology and historical geography. Ptolemy's coordinates place Rhapta at roughly seven degrees south latitude along the East African coast, and that alignment with Mafia Island has made it a serious candidate for decades. The researcher Alan, who appears on camera with Gates, describes Rhapta as 'a real place' that has been lost, distinguishing it emphatically from the mythology surrounding Plato's Atlantis: 'There's no question this was a real place, and it's gone.'
Mainstream scholarship situates Rhapta within the broader context of ancient Indian Ocean trade, a network that connected East Africa with Arabia, Persia, and the Indian subcontinent centuries before European contact. The Swahili Coast, including Mafia Island and its archipelago, was deeply embedded in these routes. Archaeologists working in the region have long noted that rising sea levels and coastal erosion over two millennia could plausibly have submerged or destroyed settlements that once sat at or near the shoreline — which is why Alan's hypothesis, as conveyed to Gates, focuses on the seafloor near Mafia Island rather than the island's interior alone.
The precise location of Rhapta remains genuinely unresolved within the scholarly community. Multiple sites along the Tanzanian and Kenyan coast have been proposed over the years, and the absence of a confirmed archaeological assemblage definitively linked to Ptolemy's description means the debate is still very much open. The fact that two separate archaeology teams were independently working on Mafia Island at the time of Gates' visit underscores the seriousness with which researchers are approaching this question.
Gates' episode in Season 13 does not claim to have solved the mystery — consistent with how the show approaches genuinely open investigations. What the episode contributes is a vivid on-the-ground portrait of active fieldwork in a remote and under-visited part of the world, connecting a general audience to a real archaeological puzzle that most people have never heard of. Whether any of the teams' findings during filming brought the search meaningfully closer to an answer is not confirmed in the available evidence.
Despite sharing its name with the infamous criminal organization, 'Mafia' in Swahili simply means 'a pleasant place to live' — a fact Gates jokes about on camera when he quips it 'sleeps with fishes.'
Mafia Island is the third largest island in Tanzanian ocean territory, according to Wikipedia, yet is administratively separate from the semi-autonomous region of Zanzibar.
The island's population is over 65,000, but Gates notes on camera it covers roughly six times the area of Manhattan while hosting only about 3% of Manhattan's population — giving it a sense of genuine remoteness.
Mafia Island is part of an archipelago and is sometimes called Chole Shamba in Swahili, meaning 'Chole farmlands,' to distinguish it from the historic settlement of Chole Mjini on the separate Chole Island inside Mafia Bay.
Mafia Island is generally accessible to visitors via small aircraft or ferry from Dar es Salaam on the Tanzanian mainland, with Kilindoni serving as the island's main hub. The island's tourism infrastructure is modest and oriented toward diving, fishing, and nature tourism rather than large-scale historical attractions, so travelers should check current local transport and accommodation options before visiting. Archaeological sites associated with the Rhapta search are active research areas and may not be open to the general public.
Dar es Salaam, Tanzania, approximately 160–180 km to the north by sea.
The dry seasons — roughly June through October and December through February — are generally considered the most comfortable times to visit, with calmer seas and clearer conditions favorable for diving and boat travel. The long rains from March through May can make coastal access more difficult.
Indian Ocean
The Indian Ocean trade network is the ancient commercial system that made Rhapta significant — Mafia Island's entire historical importance is tied to these maritime routes.
Kingdom of Kush Pyramid Tombs
The Kingdom of Kush represents another major African civilization whose archaeological record Gates has investigated, connecting to the broader theme of lost or underexplored African history.
Dwarka
Dwarka is another submerged or partially submerged ancient city that Gates has investigated, paralleling the hypothesis that Rhapta may lie beneath the waters near Mafia Island.
Alexandria
Alexandria was a hub of ancient geographical knowledge, including the works of Ptolemy whose coordinates for Rhapta directly anchor the search at Mafia Island.
Historical data sourced from Wikipedia