The island of Bali is a well-known tourism destination in Indonesia. Bali is part of the Coral Triangle, the triangular area of tropical marine waters with an incredibly high biodiversity of marine species, containing at least 500 species of reef-building corals. This makes for world-class diving where travelers can explore beautiful and unique reefs right off the coast of the island. Other popular water activities include surfing, sailing, yachting, white-water rafting and sport fishing.