The Mentawai Islands are a chain of more then seventy islands and islets on the Indian Ocean located approximately 150 km from the west coast of Sumatra, Indonesia. The strait that separates them from Sumatra is the Mentawai Strait. Siberut (4.030 km ²) is the largest island. The other major islands are Sipura, North Pagai (Pagai Utara) and South Pagai (Pagai Selatan) and the indigenous inhabitants of the islands are known as the people of the Mentawais. The Mentawai Islands have become a major surfing destination in the world during the last decade.