Zanzibar is a semi-autonomous region of Tanzania in East Africa. It is composed of the Zanzibar Archipelago in the Indian Ocean, 25–50 kilometres (16–31 mi) off the coast of the mainland, and consists of many small islands and two large ones: Unguja (the main island, referred to informally as Zanzibar) and Pemba Island. The capital is Zanzibar City, located on the island of Unguja. Its historic centre is Stone Town, which is a World Heritage Site. Zanzibar is a major holiday destination known for its beautiful beaches. This island has some of the best beaches in the world with varying surf depending on what side of the island you are on. Visitors will find soft white sand and clear shallow water, along with traditional boats.