The Amazing Emerald Cave behind the sheer cliff of Koh Muk. Tourist has to wear life jackets and swim slowly through small cavity to the cave about 70 meters. However this cave is available to visit only at low tide. Inside the Emerald Cave is beautiful as its name by the emerald water and white sand beach, surrounded by high cliff and covered by the blue sky. This is one of the wonderful natures, which cannot find anywhere in Thailand. It's a worth visiting while staying at Lanta Island,