Located on the south-east side of Hạ Long Bay, Dau Be Island is 500 meter west of Hang Trai Island, and 28 km from the Bai Chay Tourist Wharf.
Covering an area of 22,863 square km, the island is a very popular swimming and diving spot because its rich coral and deep grottoes with three inland lakes. The grottoes and caves can only be visited by rowing boat at low tide, when access is possible. Ba Ham Lake is one of the most famous spots on Dau Be Island, comprising three wide and round pits, linked together by a narrow and meandering tunnel.
Stalactites hang from the ceiling in a myriad of strange, coloured forms. There are many species of plants on the island such as benjamin figs, orchids, banyans and cycads, which blossom all year round.
Dau Be Island is also the home of yellow-haired monkeys, birds, flying squirrels and bats.