Koh Tachai is an island in the world famous Similan Islands. It is an idyllic location in the Andaman Sea with white sandy beaches and azure crystal clear water. The island is located 40km due west from Koh Phra Thong. Blue Guru Diving is the closest PADI dive centre to this scuba diving mecca. It is about 570 km south of Bangkok and 130 km north of Phuket.