What is actually standing
The authoritative description of the ruins on Chole is short, and it is worth starting from it rather than from the inventory that circulates. Mafia Island Marine Park’s management plan says that the ruins of the German two-storey boma and the promenade still dominate the landing beach. That is what you see when the boat comes in.
Around it are the remains of a settlement that grew after Kua was destroyed early in the nineteenth century and was bought by German colonialists in 1890, then abandoned as a headquarters in 1913 when the administration moved to Kilindoni. Ruined mosques on the island are attributed to the fourteenth century; most of the other standing remains are considerably more recent, from the eighteenth century onwards.
Here is where to be careful. Excursion copy gives a confident inventory — a customs house, a merchant’s house, a prison, a jail — and none of those buildings is named in any source with authority behind it. The German boma and the promenade are documented. The rest are descriptions passed between listings, and a guide naming a function for each ruin is going beyond what anyone has published.
What protects them
More than most visitors assume. The marine park’s plan states that all historical and cultural sites in the park have been given the status of core zones, in which new development is prohibited outright. Ownership rests with the Tanzanian government and management with the Antiquities Division of the Ministry of Natural Resources and Tourism, and the plan records that rehabilitation work on the German boma and other ruins on Chole was carried out with the Antiquities Division’s approval.
The condition is nonetheless recorded as endangered, which is what a coral-rag building in a wet climate with trees growing out of it generally is.
The fig trees
The image that sells this site is ruins standing under enormous strangler figs. The trees are certainly there — but the marine park’s own account of clearing shrubs, thickets and strangling figs from ruins attaches that work to Kua on Juani, not to Chole. It is a small point and it matters mainly if you are choosing which ruin to visit for the photograph.
Visiting
The ruins are a short walk from the landing beach and there are no roads or vehicles on the island, so this is a walk through a working village rather than a site visit. There is a signboard culture developing at the park’s heritage sites but no museum here.
The island’s own history — how a small island in a bay came to give its name to the whole archipelago, and lost it again — is on the Chole Island page. The archaeological tours guide covers how Tanzania’s ruins are visited, and Swahili cultural tours the wider coastal story.
Common questions about the Chole ruins
What can I actually see?
The ruins of a German two-storey boma and a promenade dominating the landing beach, with other ruined buildings around them — ruined mosques attributed to the fourteenth century, and later remains from the eighteenth century onwards.
Is there a customs house and a prison?
They are named in excursion copy and in no authoritative source. What is documented is the boma and the promenade. Treat a guided identification of each ruin’s function as a story rather than a record.
Are they protected?
Yes, twice over. They are government-owned and managed by the Antiquities Division, and every historical and cultural site inside Mafia Island Marine Park is a core zone in which new development is prohibited. Their condition is nonetheless recorded as endangered.
Is this the same as the Kua ruins?
No. Kua is on Juani Island, is much older and much larger, and was a town rather than a colonial administrative centre. It has its own page.