Geographical position

Ha Long Bay is located in the northeast corner of Viet Nam, 165 km from Ha Noi. In the Province of Quang Ninh. Ha Long Bay covers an area of 1,553 km² with 1,969 islands, of which 90% are limestone islands. To the west and north west, Ha Long Bay stretches from Yen Hung district in Ha Long city to Cam Pha town in Van Don district; to the south-east and in the south, Ha Long Bay borders the western shore of Tonkin Gulf; to the southwest the Bay borders Cat Ba island (Hai Phong province).

In 1962, Ha Long Bay was recognized as a vestige and beauty spot of national significances by Ministry of Culture and Information of Viet Nam and was also recognized as a world national heritage site twice by UNESCO organization. The first time, in 1994 for the exceptional and universal value of the landscape and the second time in 2000 for the special value of geology and geomorphology. 

Ha Long Bay’s center area was regognized as a world heritage area by UNESCO and covers an area of 434 sq. Km, including 775 islands, of which 411 are named. It is bound by Dau Go island( in the west), Dau Be island (in the south) and Cong Tay island(in the east).

A buffer zone lies around the World Heritage Area, the width is about 5 - 7 km from the protection line to the sea , on moving scale of 1-2 km.

Climate

The  climate of Ha Long Bay is tropical, being wet and hot. It is devides into four  main seasons: winter is from November to March of following year, the temperatures drop to between 15oC - 20oC. Summer is from May to September, the temperatures increases to between 26oC-27oC Two others seaons: Spring and Autumn, climate is cool. The annually  average temperature between 18oC - 19oC.

Annual rainfall averages from 2.000mm- 2.200mm. The salinity of seawater divides into between seasons: rainy season 21‰-22‰, dry season 32‰-33‰.. The bottom of bay is quite flat with the average depth of 5 -10m, in some parts 15-29m depth. There are narrow passages such as: Cua Luc(20m), The Vang(22-27m) and the others with 9-10m depth. Thanks to the system of islands and islets, the waves in Ha Long Bay are quite light, here is a uniform daily tide vanation of 3,5-4m. The low spring tides in March, April, August and December, the highest tide is in January, June, July and December.

History of the name”Halong”

The name Ha Long is literally translated as “Descending Dragons”. Prior to the 19th century, this name was not recorded in any documents or archives. When mentioning the present-day Ha Long Bay, old historical books often referred to them as the seas of Giao Chau, Luc Chau, Luc Thuy, Van Don, Hai Dong or An Bang. Not until the late 19th century did the name Ha Long Bay appear on the Bac Bo Gulf (Tonkin Gulf) chart of the French.

So when did the name Ha Long Bay originate? A legend has been handed down in the local area relating to the name Ha Long Bay, which says:

“Long ago, in the first founding days, the Viet people were attacked by foreign aggressors. The Jade Emperor sent the Mother Dragon and a herd of Child Dragons to help the Viet fight the invaders. While the enemy vessels were launching massive attacks against the mainland, the dragons descended in flocks from the sky. They spat out innumerable pearls which, in a moment, were changed into innumerable stone islands linked together into a firm citadel that checked the enemy’s advance and smashed their vessels into pieces.

After the invaders were driven out, Mother Dragon and her Child Dragons did not return to Heaven but stayed on earth, right at the place where the battle occurred. The spot where the Mother Dragon landed was Ha Long, and where the Child Dragons came down was Bai Tu Long. The place where their tails violently wagged was called Long Vi( present Tra Co peninsula).

The Legend glued to the orgination of children of the Fairy and the Dragon. Dragon and fairy symbilized to the traditional strength of fatherland and the poetic name of this area , which named by the local people. Nowadays, many names of islands and islets on Halong Bay contains Dragon(Rong) like: Dau Rong(Dragon head), Mat Rong(Dragon eyes), Hon Rong(Dragon Islets), Cai Rong anf faraway Long Chau, Bach Long Vi(White Dragon tail).