in the northwest of Chao Mai National Park Located in the area of Koh Libong Sub-district. It is about 9 kilometers from Khuan Tung Ku Port. It is the third largest island in Trang Province. Most of the area is high cliffs. Popular people come here to see the Emerald Cave. which must take a long-tail boat of the villagers Go around the back side of the island and then have to float and dive into it.