Small isolated islands of Roti, Savu, Raijua and Ndao offer much for those interested in traditional culture. These islands are unusual for their people's extensive use of the lontar palm tree. With little rainwater, people depend on a drought-resistant lontar, for nutrition when there was no other food available. Lontar is also used for building materials and for clothing. On Savu, the customary faith and customs are maintained despite professed Christianity. Cultural and religious life, based on the lunar calendar, is rich and varied, including rites of passage, sea-worm festivals, harvest festivals and violent battles with stones. Adherence to the old customs is even stronger on Raijua Island, which is considered the source of animist beliefs of the Savu island. The island Roti is stunning, with transparent water, rock formations and offshore islands with white beaches. The majority of inhabitants are farmers, cultivating rice, corn, sorghum and mung beans. The island offers a diversity of landscapes, even though it is only 1,280 km2 of land. The soil varies from black to rust to pale white, the islands has also several, not deep lakes. The island of Ndao is famed for its travelling jewellers. During the dry season they travel to Roti, Savu, Sumba or Flores, there they make jewellery for which they exchange in rice and small animals.