Hạ Long Bay (literally: "Descending Dragon Bay"; Vietnames: Vịnh Hạ Long) is a UNESCO World Heritage Site, and a popular travel destination, located in Quang Ninh province, Vietnam. Administratively, the bay belongs to Ha Long City, Cam Pha town, and part of Van Don district. The bay features thousands of limestone karsts and isles in various sizes and shapes. Hạ Long Bay is a center of a larger zone which includes Bái Tử Long bay to the northeast, and Cát Bà islands to the southwest. These larger zones share similar geological, geographical, geomorphological, climate, and cultural characters.
Hạ Long Bay has an area of around 1,553 km2, including 1,960 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.
Historical research surveys have shown the presence of prehistorical human beings in this area tens of thousands years ago. The successive ancient cultures are the Soi Nhụ culture around 18,000-7000 BC, the Cái Bèo culture 7000-5000 BC and the Hạ Long culture 5,000-3,500 years ago.Hạ Long Bay also marked important events in the history of Vietnam with many artifacts found in Bài Thơ Mout, Đầu Gỗ Cave, Bãi Cháy.
500 years ago, Nguyen Trai praised the beauty of Hạ Long Bay in his verse Lộ nhập Vân Đồn, in which he called it "rock wonder in the sky". In 1962, the Ministry of Culture, Sports and Tourism of Vietnam listed Hạ Long Bay in the National Relics and Landscapes publication. In 1994, the core zone of Hạ Long Bay was listed by UNESCO as a World Heritage Site according to criterion vii, and listed for a second time according to criterion viii.
According to local legend, when the Vietnamese were fighting Chinese invaders, the gods sent a family of dragons to help defend the land. 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. The people kept their land safe and formed what later became the country of Vietnam. After that, dragons were interested in peaceful sightseeing of the earth, and then decided to live here. 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- colour of the foam made when Dragon's children wriggled, Long: dragon, Vỹ: tail).
Hạ Long Bay is located in northeastern Vietnam, from E106°56' to E107°37' and from N20°43' to N21°09'. The bay stretches from Yên Hưng district, past Ha Long city, Cam Pha town to Van Don district, bordered on the south and southeast by the Gulf of Tonkin, on the north by China, and on the west and southwest by Cat Ba island. The bay has a 120 km long coastline and is approximately 1,553 km² in size with about 2000 islets. The area designated by UNESCO as the World Natural Heritage Site incorporates 434 km² with 775 islets, of which the core zone is delimited by 69 points: Đầu Gỗ island on the west, Ba Hầm lake on the south and Cống Tây island on the east. The protected area is from the Cái Dăm petrol store to Quang Hanh commune, Cẩm Phả town and the surrounding zone.
The climate of the bay is tropical, wet, sea islands, with two seasons: hot and moist summer, and, dry and cold winter. The average temperature is from 15°C- 25°C, and annual rainfall is between 2000mm and 2200mm. Hạ Long Bay has the typical diurnal tide system (tide amplitude ranges from 3.5-4m). The salinity is from 31 to 34.5MT in the dry season and lower in the rainy season.
Soi Nhụ culture (16,000- 5000 BC)
Located in Hạ Long and Bái Tử Long are archaeological sites such as Mê Cung and Thiên Long. There are remains from mounds of mountain shellfish (Cyclophorus), spring shellfish (Melania), some fresh water mollusk and some rudimentary labour tools. The main way of life of Soi Nhụ's inhabitants included catching fish and shellfish, collecting fruits and digging for bulbs and roots. Their living environment was a coastal area unlike other Vietnamese cultures, for example, like those found in Hoà Bình and Bắc Sơn.
Cái Bèo culture (5000- 3000 BC)
Located in Hạ Long and Cát Bà island, its inhabitants developed to the level of sea exploitation.
History shows that Hạ Long Bay was the setting for local naval battles against Vietnam's coastal neighbors. On three occasions, in the labyrinth of channels in Bach Dang river near the islands, the Vietnamese army stopped the Chinese from landing. In 1288, General Tran Hung Dao stopped Mongol ships from sailing up the nearby Bach Dang River by placing steel-tipped wooden stakes at high tide, sinking the Mongol Kublai Khan’s fleet.
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.
System of isles and caves
The bay consists of a dense cluster of over 3,000 limestone monolithic islands (although locals claim there are only 1,969 as this is the year of Ho Chi Minh’s death), each topped with thick jungle vegetation, rising spectacularly from the ocean. Several of the islands are hollow, with enormous caves. Hang Đầu Gỗ (Wooden stakes cave) is the largest grotto in the Hạ Long area. French tourists visited in the late 19th century, and named the cave Grotte des Merveilles. Its three large chambers contain large numerous stalactites and stalagmites (as well as 19th century French graffiti). There are two bigger islands, Tuan Chau and Cat Ba, that have permanent inhabitants. Both of them have tourist facilities including hotels and beaches. There are a number of beautiful beaches on the smaller islands.
Some of the islands support floating villages of fishermen, who ply the shallow waters for 200 species of fish and 450 different kinds of mollusks. Many of the islands have acquired their names as a result of interpretation of their unusual shapes. Such names include Voi Islet (elephant), Ga Choi Islet (fighting cock), and Mai Nha Islet (roof). 989 of the islands have been given names. Birds and animals including bantams, antelopes, monkeys, and lizards also live on some of the islands.
Almost all these islands are as individual towers in a classic fenglin landscape with heights from 50m to 100m, and height/width ratios of up to about six.
Another specific feature of Halong Bay is the abundance of lakes inside the limestone islands. For example, Dau Be island has six enclosed lakes. All these island lakes occupy drowned dolines within fengcong karst.
A community of around 1,600 people live on Hạ Long Bay in four fishing villages: Cửa Vạn, Ba Hang, Cống Tàu and Vông Viêng in Hùng Thắng commune, Hạ Long city. They live on floating houses and are sustained through fishing and marine aquaculture (cultivating marine biota).
Awards and designations
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, and its World Heritage Listing was updated.
In 2009, the New 7 Wonders Foundation, which runs the New Seven Wonders of the World program, included Halong Bay on its list of nominations as one the World's 7 Natural Wonders.
History of tectonics
According to scientists, Hạ Long Bay has experienced at least 500 million years in various geological states of orogeny, marine transgression and marine regression. During the Ordovician and Silurian periods (500-410 million years ago), Hạ Long Bay was deep sea. During the Carboniferous and Permian periods (340-250 million years ago), Hạ Long Bay was at shallow sea level.
Karst geomorphology value
Due to a simultaneous combination of ideal factors such as thick, pale, grey, and strong limestone layers, which are formed by fine-grained materials; hot and moist climate and slow tectonic process as a whole; Hạ Long Bay has had a complete karst evolution for 20 million years. There are many types of karst topography in the bay, such as karst fiekd.
Timeline of geologic evolution
Some of the most remarkable geological events in Hạ Long Bay’s history in the last 1,000 years, include the advance of the sea, the raising of the bay area, strong erosion that has formed coral, and, pure blue and heavily salted water. This process of erosion by seawater has deeply engraved the stone, contributing to its fantastic beauty. Present-day Hạ Long Bay is the result of this long process of geological evolution that has been influenced by so many factors.
Due to all these factors, tourists visiting Hạ Long Bay are not only treated to one of the natural wonders of the world, but also to a precious geological museum that has been naturally preserved in the open air for the last 300 million years.
The area, which now forms Hạ Long Bay, was basically mainland, submitted to a process of rain erosion.
Oedovician and Silurian periods
The area of north-east Vietnam was basically a deep sea, submitted to the constant activity of tectonic plates.
end of the Silurian period
It underwent a phase of inverse-motion that created mountains deep under the water.
end of the Silurian period and throughout the whole Devonian period
The area was subjected to powerful forces of erosion from the hot and dry climate. At this point, Hạ Long was part of a wide mainland that comprised most of today's East Sea and Chinese continental shelf.
end of the Devonian period
Due to tectonic activity, the Hạ Long area and the entire north-east region were raised from the depths
later Carboniferous and Permina periods
The formation of the limestone layer more than 1,000 m thick. A shallow and warm sea reformed, which existed for approximately 100 million years. It created two kinds of limestone: the Cát Bà layer of the early Carboniferous period (450 m thick); and the Quang Hanh layer of the middle Carboniferous and the early Permian period (750 m thick). These two layers constitute the majority of the islands of the Bay.
end of the Cretaceous period
Hạ Long Bay existed in the environment of a high mountainous mainland due to the influence of strong mountain-forming phases.
middle of the Paleocene period
These motions remain continuous and stable, while strong processes of erosion began, and after millions of years, a form of semi-highland topography took shape. The continuation of this erosion has progressively cut the highlands into blocks with altitudes similar to today's mountains
The development of the Hạ Long depression
Pleistocene epoch of the Quaternary period
The process of erosion began dissolving the limestone-rich region of Hạ Long, after that, forming the limestone plain was most active
middle and late Pleistocene epoch
Period when the caves and grottoes of the area formed.
early Holocene period
The islands of today’s Hạ Long Bay are basically remnants of these mountains, flooded. Rainwater flowed into crevices in the limestone that had formed from tectonic activity. This steady erosion constantly widened the cracks, eventually creating today's formations.
This period is notable for the advance of the sea.
The movement of the sea reached its peak and forming today’s Hạ Long Bay.
With the sea in a steady process of recession, Hạ Long culture began to develop.
beginning of the late Holocene epoch
Holocene epoch The level of the water once again increased, forming a marshy floor of canals and streams, and creating the water marks that can be seen on the stone cliffs of today.
Halong Bay is host to two ecosystems: a tropical, moist, evergreen rainforest ecosystem; and a marine and coastal ecosystem. The bay is home to seven endemic species.
- Livistona halongensis
- Impatiens halongensis
- Chirita halongensis
- Chirita hiepii
- Chirita modesta
- Paraboea halongensis
- Alpinia calcicola
The many islands that dot the bay are home to a great many other species, including (but likely not limited to): 477 magnoliales, 12 pteris, 20 salt marsh flora; and 4 amphibia, 10 reptilia, 40 aves, and 4 mammalia.
Seafood in Hạ Long is diversified. Cuttlefish- mực, oyster- hào, cyclinae- ngán, prawn (penaeidea- tôm he, panulirus- tôm hùm, parapenaeopsis- tôm sắt...), sipunculoideas- sá sùng, nerita- ốc đĩa, charonia teritonis- ốc tù và, and cà sáy, are among the varieties appearing in popular local dishes.
With an increasing tourist trade, mangroves and seagrass beds have been cleared and jetties and wharves have been built for tourist boats.
Fuel and oil, along with tourist litter, have created pollution problems, which impact on both the aquatic and terrestrial ecosystem of the islands. Human waste from portable toilets erected for tourists, finds its way into the soil and water surrounding the islands, once more altering the ecosystem functioning, through increased nutrient flow.
Game fishing, often near coral reefs are threatening many endangered species of fish. Often fish caught in the bay are not consumed locally but exported to other markets around the region.
The delicate limestone cave ecosystems are diminishing as tourists visiting the caves break off stalagmites and stalactites. Litter, including wine bottles, are dropped into cave streams. Visitors exhale carbon dioxide, which has a deleterious effect on the caves. The mouths of some caves have been widened to allow for tourist access. This increase in light has led to an imbalance in the delicate links between flora and fauna, and a decrease in the humidity of the caves.