Tien Cong Cave is located only 4 kilometers from the harbor north of Dao Gu Island in the southwest of Halong Bay. The story of this cave is interesting, as until 1993 it was considered a place of legend, and today it provides an insight into the history of myths and magical stories in the Vietnamese culture, it is also a popular stop for the best cruises, and when you reach the cave you will be rewarded with unique and beautiful spaces lit with lights and mysterious colors that give it a glow from another world.