| This uninhabited island lays northeast nearly exactly half way between Similan Nr. 9 and Surin Island. It s about two hours drive from Similan to Koh Tachai. Koh Tachai;s southeast tip is called twin peaks; two pinnacles connected by a reef. Explore gigantic rock formations and plateaus. This site is well known for its beautiful hard and soft corals, schools of bathfish and large creatures like wale sharks, mantas, big rays, leopard sharks and reef sharks. Stong currents make this a good place for huge sea fans.