Dating back to the late 13th century and abandoned in the early 1600s, this is yet another mysteriously little-recorded medieval ruin, considered by many to be the best example of its kind in East Africa. We're not talking Pompeii here, but there is some clear semblance of a profoundly organized and efficient society that built a proper town and went to pains to establish at least seven mosques and some very decent toilets. Why precisely the town was abandoned is uncertain, although, given the circumstances of the entire East African coast during the 17th century, it can almost be assumed that the city was attacked and plundered, leaving the forest to take hold and create the evocative site that remains today. What is known is that the people -- who followed an adapted form of Islam -- had trade links with China, Phoenicia, and Europe, evident from the types of artifacts unearthed here (these can be seen in the little museum). Today Sykes' monkeys live in the trees around the ruins, and it's possible to see other small animals here, including the golden-rumped elephant shrew.