Ha Long Bay is located in northeastern Vietnam in Quang Ninh Province, 165km from Hanoi. Halong Bay covers an area of 1,553 km2, including 1,969 islands (980 of which are named). North and northwest extend from Quang Yen town, through Ha Long City, Cam Pha City to the end of Van Don Island; In the southeast and south, it borders on the West Bank of the Gulf of Tonkin, in the southwest it borders Cat Ba Island (Hai Phong).
The UNESCO-designated DSTG area covers an area of 434 km2, including 775 islands, of which 411 are named. This is a place where many famous islands, caves and beaches are located.