Zanzibar sits on ancient coral rock, and where the rock has collapsed inward the island has opened up a set of natural freshwater caves. Three of them are open to visitors and each has its own character: Kuza Cave near Jambiani, tied to Swahili cultural heritage; Maalum Cave near Paje, a deep blue swimming pool under an open roof; and Salaam Cave at Kizimkazi, small, dark and lit by candlelight.
The water in the caves is fresh, cool and still, filtered through the coral rock. Swimming in them is a different experience from the ocean and a welcome break from the heat.
The tour pairs the caves with a visit to the natural turtle aquarium, a large tidal pool set in the coral rock behind the beach. It began as a rehabilitation and study site for marine turtles and now works to protect the local population. A keeper explains the work, and you are able to feed the turtles seaweed or get into the pool for a closer encounter.
The visit takes two to three hours and works well as a half-day for guests staying on the east or south coast.