Hạ Long Bay is located in northeastern Vietnam, from E106°56' to E107°37' and from N20°43' to N21°09'. The bay stretches from Yên Hưng district, past Hạ Long city, Cẩm Phả town to Vân Đồn district, bordered on the south and southeast by the Gulf of Tonkin, on the north by China, and on the west and southwest by Cát Bà island. The bay has a 120 km long coastline and is approximately 1,553 km² in size with about 2,000 islets. The area designated by UNESCO as the World Natural Heritage Site incorporates 434 km² with 775 islets, of which the core zone is delimited by 69 points: Đầu Gỗ island on the west, Ba Hầm lake on the south and Cống Tây island on the east. The protected area is from the Cái Dăm petrol store to Quang Hanh commune, Cẩm Phả town and the surrounding zone
