Bai Tu Long Bay comprises hundreds of islands in both big and small sizes. They belong to two types: lime-stone islands and schist islands. The islands of Bai Tu Long are the result of tectonic process over 300 million years. Many of them are well-known tourism islands such as Quan Lan Island, Minh Chau Island, Ngoc Vung Island, and The Vang Island. Karst corrosion process and weathering created several amazing caves, especially Quan Cave (Navy Cave).
Bai Tu Long Bay has a rich biodiversity with typical ecosystems: mangrove ecosystem, coral reef ecosystem, ecosystem of tropical forests. It is home to various species of flora and fauna. There are 780 species of flora in Bai Tu Long Bay and 21 species among them are included in the list of Vietnam’s Red Data Book. Scientists also found 931 species of aquatic animals there. In 2001, Bai Tu Long National Park was established with the area of 14 ha in order to preserve biodiversity in this region.
Bai Tu Long Bay has the total population of 30.000 people whose livelihoods depend mainly on farming and fishing. On Bai Tu Long, there remain many archaeological relics of Halong Culture (dating around 3.000 – 2.000 BC) and historical trails of the ancient Van Don commercial port (in 13th century).