Halong Bay Facts: Top 10 Intriguing Things!

There are many Halong Bay facts that you might have never heard of. These interesting things can help you understand more deeply about the culture as well as the history of Halong Bay and its local people. Moreover, these are not just short, general facts, but cool and specific ones.

top 10 fun halong bay facts

Fact No.1: Etymology

  • The name “Hạ Long” is derived from the Sino-Vietnamese, which means “descending (Hạ) dragon (Long)”.
  • According to local legend, to assist the Vietnamese in defending their country, the gods sent a family of dragons as protectors. The place where the mother dragon descended was named Hạ Long, the place where the dragon’s children attended upon 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)
  • Many of the islands are named after their unusual shapes: Voi (elephant) Islet, Ga Choi (fighting cock) Islet, Khi (monkey) Islet, and Mai Nha (roof) Islet, etc.

As you can see, all the names are really straightforward, self-explanatory and easy to remember. Simple but interesting, right?

Fact No.2: Geography

  • Hạ Long Bay has an area of around 1,553 km2, including 1,969 (you are not reading it wrong) islands and islets.
  • The bay extends 120 kilometers along the coastline.
  • The core (where most Halong Bay cruises visit) of the bay has an area of 334 km2 with a high density of 775 islets which is a triangle formed by 3 corners: Đầu Gỗ island, Ba Hầm lake and Cống Tây island.

It is easy to get lost in the middle of this triangular matrix of beauty and greatness but it is worth your adventure!

Fact No.3: Climate

  • Many websites say that Halong Bay has 4 different seasons. In fact, there are only 2 major ones: hot and moist Summer, and cool and dry Winter.
  • The average temperature is from 15 °C- 25 °C, and annual rainfall is between 2 meters and 2.2 meters
  • Hạ Long Bay has the typical diurnal tide system, tide amplitude ranges from 3.5-4m.

With some “light and simple” packing, you can start your adventure to Halong Bay in March, best time to visit because it is the end of winter. Check out this complete guide of Halong Bay weather throughout the year.

Fact No.4: History

  • Halong Bay was the setting for successful Vietnamese naval battles against 3 coastal invasions of Mongol enemies in the Feudal period.
  • During the Vietnam War, many of the channels between the islands were heavily mined by the United States navy, some of which pose a threat to shipping to this day.

All of Vietnamese students are taught about the victory of the epic fight against Mongol enemies. in Vietnam, history is a compulsory subject and most of the students and I do not like it. However, I must admit Halong Bay contributed greatly to the freedom of Vietnam today!

Fact No.5: Archaeology

  • Halong is not only a natural wonder but also the habitat of prehistoric man. This Halong Bay fact was found out when a man named Vũ Xuân Tảo came across a stone axe while fetching material for his work
  • There were 3 major cultures in the Bay: Soi Nhụ culture (16000 – 5000 BC), Cái Bèo culture (5000 – 3000 BC) and Halong (3500 – 5000 years ago).

Fact No.6: Population

  • About 1540 people are living in fishing villages like Cửa Vạn, Ba Hang, etc. They stay on boats or floating houses that are sustained through fishing and marine aquaculture.
  • About 40 out of 1969 islands are being inhabited by local fishermen. They have been turning wild islands into habitable and rich areas such as Sa Tô island or Thắng Lợi island.
  • To develop the tourism industry and improve life quality, more than 300 households have been encouraged to move onto land.
  • However, there are many traditional fishing villages that are maintained for tourists to visit.
Halong Bay facts - population
Cua Van floating village

Fact No.7: Islands

  • Most of the islands and islets in Halong Bay are made of limestone which has gone through 500 million years of formation
  • With heights ranging from 50-100 meters and a height-to-width ratio of about 6:1, the majority of these karst pinnacles and islets have sheer, vertical cliffs.
  • There are 1969 islands and islets; only 989 have names and 980 ones left unnamed.
  • Many of the wild islands are totally untouched because of their steep and sharp edges and ridiculous heights which make it too dangerous to explore.
Halong Bay facts - islands
Halong Bay islands

Fact No.8: Caves

  • There are 3 main types of caves: Old phreatic caves (Sung Sot, Tam Cung, Lau Dai, Thien Cung), Old karstic foot caves (Trinh Lu, Bo Nau, Tien Ong) and Marine notch caves
  • The most famous caves in Halong Bay are Heavenly Residence Cave (Thien Cung), Surprise Cave (Sung Spot), Driftwood Cave (Dau Go) and Three Palace Cave (Tam Cung). The caves in Halong Bay are some of the most spectacular in the world. However, a number of others are not opened to visitors in an attempt to preserve their integrity.
  • Sung Sot (Surprising) Cave has another French name “Grotte des surprises”
  • Đầu Gỗ Cave was the storage of the remnants of sharp wooden columns built under the water level for the Vietnamese naval fight against Mongolian invaders’ ships.
  • There is no exact number of all the caves in Halong Bay.
Halong Bay facts - caves
Sung Sot Cave – Supprise Cave

Fact No.9: Biodiversity

  • Oceanic and seashore bio-system with common aquatic species found in the bay include: cuttlefish, oyster, prawns, panulirus, etc.
  • tropical evergreen bio-system in this region with more than 1000 plant species
  • The many islands that dot the bay are home to a great many other species: magnoliales, amphibia, mammalia, etc.

Although there are many types of animal, I have never seen a single one on all my trips to Halong Bay (except birds and squids from night fishing activity on the cruises)

Fact No.10: Awards

  • In 1962, the Vietnam Ministry of Culture, Sport and Tourism designated Hạ Long Bay a ‘Renowned National Landscape Monument’.
  • Hạ Long Bay was first listed as a UNESCO World Heritage Site in 1994, in recognition of its outstanding, universal aesthetic value.
  • In 2000 the World Heritage Committee additionally recognised Hạ Long Bay for its outstanding geological and geomorphological value.
  • In 2012, New 7 Wonders Foundation (not a UNESCO event, not recognized by UNESCO) officially named Halong Bay as one of New Seven Natural Wonders of the world.

There was a fun fact that from 2007 to 2011, many Vietnamese people mistook that the New 7 Wonders Foundation was an autherized organization of UNESCO. Many people voted for Halong Bay only after to find out that the result was not regconized by UNESCO.


Those are all the Halong Bay facts that I can tell you. It is quite long and time-consuming and comprehensive and informative. But hey, if you reached this far, I am sure that you found these facts at least interesting, right? If you have any Halong Bay facts that I missed, share them with me and the others. And if this post is really that interesting, feel free to retweet or share on Facebook!

And to experience these facts yourself, why don’t you book a luxury cruise to Halong Bay, I would recommend Orchid Cruise and Azalea Cruise because they are the newest ones!