Sumba is one of the most interesting islands. It has neolithio decorated stone groups, traditional houses and many tribes that still live their traditional lifestyle.
Many of the villages on the islands have one or more of the giant stones that were used as burial mounts for the kings who rules the villages.
Waingapu is the main town of the island and is an excellent base for exploring the traditional villages. Prailiu is one of the nicest of these. Praiyawang, Umabara and Pau are other nice options.