Zanzibar is a semi-autonomous part of the United Republic of Tanzania, in East Africa. It comprises the Zanzibar Archipelago in the Indian Ocean, 25-50 kilometres (16-31 mi) off the coast of the mainland, and consists of numerous small islands and two large ones: Unguja (the main island, informally referred to as Zanzibar), and Pemba. Zanzibar was once a separate state with a long trading history within the Arab world; it united with Tanganyika to form Tanzania in 1964 and still enjoys a high degree of autonomy within the union. The capital of Zanzibar, located on the island of Unguja, is Zanzibar City, and its historic center, known as Stone Town, is a World Heritage Site. Zanzibar’s main industries are spices, raffia, and tourism. In particular, the islands produce cloves, nutmeg, cinnamon and pepper. For this reason, the islands, together with Tanzania’s Mafia Island, are sometimes called the Spice Islands. Zanzibar’s ecology is of note for being the home of the endemic Zanzibar Red Colobus and the (possibly extinct) Zanzibar Leopard. During the Age of Exploration, the Portuguese Empire was the first European power to gain control of Zanzibar, and the Portuguese kept it for nearly 200 years. The main island of Zanzibar, Unguja, has a fauna which reflects its connection to the African mainland during the last ice age. Endemic mammals with continental relatives include the Zanzibar red colobus, a full species; the Zanzibar leopard, which is critically endangered and possibly extinct; and the recently described Zanzibar servaline genet. Pemba island is separated from Unguja island and the African continent by deep channels and has a correspondingly restricted fauna, reflecting its comparative isolation from the mainland. Its best-known endemic is the Pemba Flying Fox. As a semi-autonomous part of Tanzania, Zanzibar has its own government, known as the Revolutionary Government of Zanzibar. It is made up of the Revolutionary Council and House of Representatives. Important architectural features in Stone Town are the Livingstone house, the Guliani Bridge, and the House of Wonders. The town of Kidichi features the hammam (Persian baths), built by immigrants from Shiraz, Iran during the reign of Barghash bin Said. Its very name evokes romantic associations – smell of spices, images of narrow streets, Arab chests, carved doors, coral reefs. It is a tourists paradise, with tranquil, warm tropical waters, many miles of beautiful sandy beaches on the Indian Ocean. On these shores passed explorers like Burton, Speke, Livingstone, and Vasco da Gama in 1502 enroute to India. Zanzibar has a rich and ancient past, having been the center for travelers sailing from distant lands of the Middle East by dhows. Zanzibar was once the main trading center for the whole of East Africa. Due to the generally slower pace of life, its tranquillity has survived. Zanzibar can be reached from Dar Es Salaam either by 30 minutes air flight or 1 1/4 hour hydrofoil or catamaran ride.