Thu 31/03/2016 | 21:14 GMT+7
Hạ Long Bay has an area of around 1,553 km2, including 1,960–2,000 islets, most of which are limestone. The core of the bay has an area of 334 km2 with a high density of 775 islets. The limestone in this bay has gone through 500 million years of formation in different conditions and environments. The evolution of the karst in this bay has taken 20 million years under the impact of the tropical wet climate.The geo-diversity of the environment in the area has created biodiversity, including a tropical evergreen biosystem, oceanic and sea shore biosystem.Hạ Long Bay is home to 14 endemic floral species and 60 endemic faunal species.
According to local legend, when Vietnam had just started to develop into a country, they had to fight against invaders. To assist the Vietnamese in defending their country, the gods sent a family of dragons as protectors. This family of dragons began spitting out jewels and jade. These jewels turned into the islands and islets dotting the bay, linking together to form a great wall against the invaders. Under magics, numerous rock mountains abruptly appeared on the sea, ahead of invaders' ships; the forward ships struck the rocks and each other. After winning the battle, the dragons were interested in peaceful sightseeing of the Earth, and then decided to live in this bay. The place where the mother dragon descended was named Hạ Long, the place where the dragon's children attended upon their mother was called Bái Tử Long island (Bái: attend upon, Tử: children, Long: dragon), and the place where the dragon's children wriggled their tails violently was called Bạch Long Vỹ island (Bạch: white-color of the foam made when Dragon's children wriggled, Long: dragon, Vỹ: tail), present day Trà Cổ peninsula, Móng Cái.