Zanzibar offers an excellent combination of shallow water reefs around the surrounding offshore islands, and high walls, deep channels and shipwrecks for the more experienced. The best and most varied diving can be found along the northeastern coast around Mnemba Island, with beautiful coral gardens and wall dives. Around March the giant but gentle whale sharks stop here on their migration and are the highlight of a dive in this atoll. Stone Town has some interesting nearby wrecks and well-preserved coral reefs. There are dive schools at many hotels and in Stone Town and Matemwe.