Pemba is an island about 50 kilometers to the north of the island of Zanzibar. Both islands are part of Tanzania and lie off the east coast of Africa in the Indian Ocean. Together with Mafia Island, they form the Spice Islands. Most of the island, which is regarded to be hillier and more fertile than Zanzibar, is dominated by small scale farming. There is large scale farming of cash crops such as cloves and there are over 3 million clove trees. The eastern side is exposed to open ocean and an ever present wind. The western side of the island is very different. Coastal waters are protected by hundreds of tiny islands an easy sail from shore. Reefs rise up from depth to the surface and are often exposed at low tide. The island is not often visited, although it is a center for traditional medicine and witchcraft. People come from as far away as Zaire to seek spiritual and physical healers.