Ha Long Bay (Vietnamese: Vịnh Hạ Long, literally: “descending dragon bay”) is a UNESCO World Heritage Site, and a popular travel destination, located in Quang Ninh province, Vietnam. Administratively, the bay belongs to Hạ Long City, Cẩm Phả town, and part ofVan Don district. The bay features thousands of limestone karsts and isles in various sizes and shapes. Ha 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 similargeological, geographical, geomorphological, climate, and cultural characters.
Ha 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. Ha 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.
The name Hạ Long is derived from the Sino-Vietnamese 下龍, meaning “descending dragon”.
According to local legend, when Vietnamese had just started to develop into a country, they had to fight against invaders. To assist Vietnamese in defending their country, the gods sent a family of dragons as protectors. This family of dragons began spitting out jewelsand 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, Mong Cai.
The bay consists of a dense cluster of over 3,000 limestone monolithic islands 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, Tuần Châu and Cat Ba, that have permanent inhabitants, as well as tourist facilities including hotels and beaches. There are a number of beautiful beaches on the smaller islands.
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), plying 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.
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 Hạ Long city, Cẩm Phả town to Vân Đồn district, bordered on the south and southeast by the Gulf of Tonkin, on the north by China, and on the west and southwest by Cát Bà island. The bay has a 120 km long coastline and is approximately 1,553 km² in size with about 2,000 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 mollusc 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.
Geology and geomorphology
History of tectonics
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 Carboniferousand 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 field.
Timeline of geologic evolution
Some of the most remarkable geological events in Hạ Long Bay’s history have occurred 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.
|570,000,000-500,000,000 BC||beginning of theCambrian era||The area, which now forms Hạ Long Bay, was basically mainland, submitted to a process of rain erosion.|
|end of the Cambrian period||The area was flooded, commencing the existence of Hạ Long Bay.|
|500,000,000-400,000,000 BC||Ordovician and Silurianperiods||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.|
|420,000,000-340,000,000 BC||end of the Silurian period and throughout the whole Devonianperiod||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 South China 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|
|340,000,000-240,000,000 BC||later Carboniferous andPermian 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.|
|67,000,000 BC||end of the Cretaceousperiod||Hạ Long Bay existed in the environment of a high mountainous mainland due to the influence of strong mountain-forming phases.|
|middle of thePaleocene 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|
|26,000,000-10,000,000 BC||Neogene period||The development of the Hạ Long depression|
|2,000,000-9000 BC||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|
|68,000-9000 BC||middle and latePleistocene 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.|
|9000-5000 BC||Holocene period||This period is notable for the advance of the sea.|
|5000-2000 BC||The movement of the sea reached its peak and forming today’s Hạ Long Bay.|
|2000-1000 BC||With the sea in a steady process of recession, Hạ Long culture began to develop.|
|beginning of the late 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 and 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, 20salt marsh flora; and 4 amphibia, 10 reptilia, 40 aves, and 4 mammalia.
Common aquatic species found in the bay include: cuttlefish (mực); oyster (hào); cyclinae (ngán); prawns (penaeidea (tôm he), panulirus (tôm hùm), parapenaeopsis (tôm sắt), etc.); sipunculoideas (sá sùng); nerita (ốc đĩa); charonia tritonis (ốc tù và); and cà sáy.
With an increasing tourist trade, mangroves and seagrass beds have been cleared and jetties and wharves have been built for tourist boats.
Game fishing, often near coral reefs, is threatening many endangered species of fish.
Local government and businesses are aware of problems and many measures have been taken to minimize tourism affect to the bay environment for sustainable economic growth 
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 October 2011, World Monuments Fund included the bay on the 2012 World Monuments Watch, citing tourism pressures and associated development as threats to the site that must be addressed. The goal of Watch-listing is to promote strategies of responsible heritage-driven development for a sustainable future.
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 New7Wonders of Nature. In 2012, the New 7 Wonders Foundation officially named Halong Bay as one of new seven natural wonders of the world.
Hạ Long Bay is also a member of the Club of the Most Beautiful Bays of the World.
In writings about Hạ Long Bay, the following Vietnamese writers said:
- Nguyễn Trãi: “This wonder is ground raising up into the middle of the high sky”.
- Xuân Diệu: “Here is the unfinished works of the Beings…Here is the stones which the Giant played and threw away”.
- Nguyên Ngọc: “…to form this first- rate wonder, nature only uses: Stone and Water…There are just only two materials themselves chosen from as much as materials, in order to write, to draw, to sculpture, to create everything…It is quite possible that here is the image of the future world”.
- Ho Chi Minh: “It is the wonder that one cannot impart to others”.
- Pham Van Dong: “Is it one scenery or many sceneries? Is it the scenery in the world or somewhere?”.
- Nguyễn Tuân: “Only mountains accept to be old, but Hạ Long sea and wave are young for ever”.
- Huy Cận: “Night breathes, stars wave Hạ Long’s water”.
- Che Lan Vien:
“Hạ Long, Bái Tử Long- Dragons were hidden, only stones still remain
On the moonlight nights, stones meditate as men do…”
Lord Trịnh Cương overflowed with emotion: “Mountains are glistened by water shadow, water spills all over the sky”.
Hạ Long bay’s inhabitants have developed numerous tales explaining names given to various isles and caves in the bay.
- Đầu Gỗ cave (literally: “the end of wooden bars” cave): these wooden bars in this cave are the remnants of sharped wooden columns prepared to build under the water level by the order of Trần Hưng Đạo commander in order to sink Mongolian invaders’ ships in 13th century.
- Kim Quy cave (literally: “Golden Turtle” cave): it is told that the Golden Turtle swam toward the Eastern Sea (international name: South China Sea) after returning the holy sword which had assisted King Lê Thái Tổ in the combat against Ming invaders from China. Next, with the approval of the Sea King [disambiguation needed], Golden Turtle continued to fight against monsters in this marine area. Unfortunately, the turtle became exhausted and passed away in a cave. Consequently, the cave was named after the Golden Turtle.
- Con Cóc isle (literally: Frog isle): is a frog- like isle. According to ancient tales, in a year of severe drought, a frog directed all animals to the Heaven and protested against the God. They demonstrated in favour of making rain. As a result, the God must accept the frog as his uncle. Since then, whenever frogs grind their teeth, the God has to pour water down the ground.