Koh Tachai is a small, uninhabited island located in the Andaman Sea, part of Thailand. It is known for its stunning white sandy beaches, crystal-clear waters, and vibrant coral reefs, making it a popular destination for snorkeling and diving enthusiasts. The island is part of the Similan Islands National Park, which is renowned for its rich marine biodiversity. Visitors to Koh Tachai can enjoy various activities such as swimming, sunbathing, and exploring the underwater world. The island is accessible by boat from nearby locations, and its natural beauty attracts tourists seeking a tranquil escape in a picturesque setting.