On Juani Island, a short boat ride from the main island, the ruins of Kua are among the most evocative Swahili ruins on the East African coast. Kua was a substantial trading town from the 14th century, part of the network of Arab-Swahili settlements that controlled the Indian Ocean trade in gold, ivory, and slaves from Zimbabwe and central Africa. At its height it was one of the more important ports in the Mafia Archipelago.
The ruins are a national historic site but are largely unmanaged. The standing structures include the remains of a double-storey building with stone staircases and the footprints of several mosques, all built in the distinctive coral-rag style of Swahili architecture. The atmosphere is genuinely atmospheric rather than museumlike — dense vegetation growing through the walls, birdsong, and occasional views of the sea. Ask at your lodge about organising a boat and a guide; Juani Island is also good for walking and birdwatching.