Hoan Kiem Lake, Vietnam

Lake Locations:

Vietnam -

Also known as:  Sword Lake, Lake of The Returned Sword, Lake of The Restored Sword

Hoan Kiem Lake is one of the best-known cultural features in Hanoi, capital of Vietnam. Located in the historical center of the city, Hoan Kiem Lake, or Lake of The Sword as it is also known, plays a major part in one of the best-loved legends of this southeast Asian city. In the war for independence from China’s Ming Dynasty, legend says that the hero Emperor Le Loi was gifted a magical sword by the Golden Turtle God which he used with success in winning the country’s independence. Some time later, while the emperor was fishing in the lake, the magic sword was grabbed by a large turtle who disappeared with it under the waves. The legend continues that the Golden Turtle God had reclaimed the sword after it had served its purpose and will reappear with it if ever needed again.

Previously, the lake was called ‘Green Lake’ due to its green color, but was renamed Ho Hoan Kiem, meaning Lake of The Returned Sword. Emperors since the 16th century have revered the lake and worked to beautify its shores. A species of huge, nearly-extinct freshwater turtle inhabits the lake and is considered sacred by the Vietnamese people. The turtles are suspected to be the species, Rafetus swinhoei (Swinhoe’s softshell turtle) or a related species, extremely rare and the largest known freshwater turtles in the world.

Located in the heart of Hanoi’s historic old city, Hoan Kiem Lake is a vital part of daily life in Hanoi. Surrounded by walkways and gardens, the shore is the site of early-morning Vietnamese visitors performing their daily exercise routines or enjoying the peaceful lake in the growing light. All day long and into the late evening, the lakeshore walkways are crowded with walkers enjoying one of the most peaceful places in the bustling city. At midnight on the first night of the Tet New Year celebration, it is traditional to explode millions of firecrackers near the shore, where the smoke drifts across the lake.

The lake is on nearly every Vietnam travel itinerary; all places in the older parts of the city are judged in distance from Hoan Kiem. One striking focal point of most lake views is the small Turtle Tower built on a tiny islet in the lake. The Turtle Tower was built on the site of a former 16th century pagoda and commands the eye from the nearby shore. It is is a well-known daily reminder of the legend of the Returned Sword. So venerated is the small tower that recent efforts to repair and repaint its weathered facade were met with massive public outcry.

Hoan Kiem Lake likely originated as a remnant of the past course of the nearby Red River, although it is now several miles away. There aren’t any obvious inflowing streams, but the lake apparently gains from ground water and is replenished by rainfall. Studies show the lake to be stagnant and the green color the result of algae growth. Locals do some fishing in the lake, but it apparently isn’t terribly productive for fish, possibly because of the unknown number of giant turtles that are seldom seen. The lake is only about 25 acres and can be circled by walking in about half an hour.

Most visitors find plenty of interesting sights along the way to stop and admire. The many emperors since the 16th century have built a number of temples and shrines which have changed names and dedications over the intervening ages. One example is the history of Khanh Thuy shrine on Ngoc island on the north end of the lake. Artificial hills, towers, shrines and bridges create a complex of temples and scenic vistas that require a good guidebook to identify them all.

North from Hoan Kiem Lake, the oldest parts of Hanoi hold a large number of cultural edifices and streets devoted to traditional craft shops and small cafes. This area is popular with tourists who are looking for ‘local color’ and who often find Vietnamese history along the route. The Temple of Literature dedicated to Confucius is the site of the Imperial Academy, Vietnam’s first national university. Directly across the street, the Vietnam Fine Arts Museum holds examples of some of the country’s finest paintings, lacquers and ceramics, along with items representing the distant past. Unfortunately, many of the items on display are reproductions, the originals having been destroyed in the VietNam War. The nearby Vietnam Museum of Ethnology celebrates the many varied cultures within the country’s borders with exhibits, outdoor models of the homes of minority groups, and traditional song and dance. The village of Bat Tang, on the suburban outskirts of Hanoi, is noted for its Bat Trang porcelain and pottery. The history of Bat Trang pottery-making can be traced back to the 14th century and has found its way on trade ships around the world. If the visit is long enough, visits can be made to some of the national parks and smaller cities in the country.

The turtles found in Hoan Kiem Lake are somewhat mysterious; some claim to see them regularly, but those sighted are likely a similar species. A preserved specimen can be seen in the Ngoc Son Temple on an island in the south portion of the lake. The last verified sighting was in 2004, when a large turtle crawled up on the island of the Turtle Tower during a period of low water. This major event alarmed local authorities enough that a major effort was undertaken to remove some of the muck from the lake bottom and pump in fresh water from nearby wells drilled for the purpose. The tortoise is one of the four sacred creatures in the animist traditions of Vietnam and considered a good luck omen, so the residents of Hanoi are willing to do nearly anything necessary to make sure their turtles continue to survive.

Hanoi is a modern city, and the newer areas contain many hotels, motels and guest houses. It is probably wise to arrange accommodations ahead of time through a reputable tourism company if one is not thoroughly conversant of the country and its language. Many visitors hire a car and driver who can act as guide. Others rent scooters to tour the back roads and visit out-of-the-way places. Lucky visitors may get a room with a view of Hoan Kiem Lake, and maybe a glimse of one of the sacred turtles.

Things to do at Hoan Kiem Lake

  • Vacation Rentals
  • Fishing
  • National Park
  • Museum

Hoan Kiem Lake Photo Gallery

Hoan Kiem Lake Statistics & Helpful Links

divider

Lake Type: Natural Freshwater Lake, Not Dammed

Surface Area: 25 acres

Shoreline Length: 1 miles

Normal Elevation (Full Pond): 34 feet

Average Depth: 4 feet

Maximum Depth: 7 feet

Spread the word! Share our Hoan Kiem Lake article with your fellow Lake Lubbers!

Trophic State | LakeLubbers

Trophic State measures the level of algae and nutrients in a lake.

An oligotrophic lake is very clear (blue in color) and does not support much plant or fish life. A hyper-oligotrophic lake is the clearest of all lakes, and is nearly devoid of plants and fish.

A mesotrophic lake is slightly green and supports a moderate degree of plant and fish life. A lake's most desired trophic state is generally this mid-point - the mesotrophic state.

A eutrophic lake is somewhat murky and supports a large amount of plant and fish life. A hypereutrophic lake is clouded with algae, plant life, and fish life. A eutrophic or hyper-eutrophic lake can be difficult to navigate by boat - and is often an unpleasant place to swim.

The use of phosphorus-rich and nitrogen-rich fertilizer on lawns and golf courses surrounding a lake can cause it to become eutrophic or hypereutrophic.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Catchment or Drainage Area | LakeLubbers

This is the surrounding area that drains into a lake, including land, rivers and their tributaries. This is also known as the lake's "catchment basin".

Small lakes at the highest peaks of mountains have small drainage areas. The world's oceans have the largest drainage areas.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Lake-Area Population | LakeLubbers

This is the estimated number of people who live in a house with a view of a lake, plus those who self-describe the lake as their home, for example: "I live at Smith Mountain Lake."


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Water Residence Time | LakeLubbers

This is the estimated time that it takes for an amount of water equal to the entire volume of a lake to flow out of - or evaporate from - the lake.

Residence Time can be as short as a few days for fast-flowing small lakes, and can exceed 100 years for slow-flowing large lakes.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Completion Year | LakeLubbers

This is the year that a reservoir was first filled to the reservoir's normal elevation - or the year that a natural lake was first dammed. A large reservoir can take more than a year to fill after its dam is first closed.

The Grand Anicut in southern India is generally considered the world's oldest dam that still operates. Grand Anicut was constructed in the second century BC. It now impounds an irrigation network that includes roughly one million acres.

You can find many of the the world's newest reservoirs on LakeLubbers. Many of the world's oldest reservoirs appear on the last page of that list.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Water Volume | LakeLubbers

This is the estimated volume of water that a lake contains -- measured at the lake's normal elevation. By this measure, the world's largest freshwater lake is Siberia's Lake Baikal.

You can find many of the the world's largest lakes (by water volume) on LakeLubbers.

Water Volume can be measured in acre-feet, in cubic miles, or in cubic kilometers. One acre-foot is the amount of water needed to cover one acre (43,560 square feet) to a depth of one foot. One cubic mile equals 3,379,200 acre-feet. One cubic kilometer equals 810,713 acre-feet.

1 acre-foot is equal to 325,851 US gallons. Siberia's Lake Baikal contains about 6,276,367,740,000,000 gallons of freshwater - nearly 1 million gallons for every living person on earth.

The other - and more widely used - measure of a lake's size is the lake's surface acreage. By that measure, the world's largest freshwater lake is North America's Lake Superior.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Maximum Depth | LakeLubbers

This is the estimated greatest depth of the water in a lake -- measured at the lake's normal elevation. The world's deepest lake is Siberia's Lake Baikal; that lake's maximum depth is estimated at 5,314 feet.

You can find many of the the world's deepest lakes on LakeLubbers. If you select the last page of that list, you will find the (maximum depth of) the shallowest lakes in our database.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Average Depth | LakeLubbers

This is the estimated average depth of the water in a lake -- measured at the lake's normal elevation. If the water volume and surface area of a lake are known, an estimate of the lake's average depth can be calculated:

Water volume ÷ Surface Area = Average Depth

Example: 1,000,000 acre-feet ÷ 20,000 acres = 50 feet average depth


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Maximum Elevation | LakeLubbers

This is a lake's highest water level, measured by the lake's surface distance above sea level, that can occur during flooding. A lake's highest possible maximum elevation is usually the top of the lake's dam or spillway.

At lakes that include residential development, government regulations usually forbid the construction of homes below a lake's maximum elevation.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Minimum Elevation | LakeLubbers

This is a lake's lowest water level, measured by the lake's surface distance above sea level, that can be reasonably expected to occur. Low lake levels can occur due to deliberate seasonal draw downs for irrigation or impending snow melt, reduced water inflows, drought and evaporation, residential or commercial water demands, and hydropower generation.

Some lakes' minimum and maximum elevations are virtually the same. Lakes that generate hydropower may vary by several feet - according to power demand. Lakes whose primary purpose is to prevent flooding can seasonally vary by 100 feet or more.

When some lakes reach their minimum elevation, their boat ramps may not be long enough to permit boat access - and boats docked on shallow parts of the lake may end up on dry ground. In those cases, kayakers and shore-based anglers may be among the few happy recreational users of the lake.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Normal Elevation | LakeLubbers

This is a lake's normal water level, measured by the lake's surface distance above sea level. For a reservoir, this water level is also known as "full pond" or "full pool".

You can find many of the world's highest-elevated lakes on LakeLubbers. Lakes with the lowest elevations (known by LakeLubbers) are shown on the final page of that list.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Shoreline Length | LakeLubbers

This is the length of the exterior shoreline around a lake - measured at the lake's normal elevation. The shoreline length can be considerably shorter or longer when lake water levels are lower or higher than normal.

A lake with many coves has a much longer shoreline than a lake of similar surface area that is nearly circular in shape.

When known, the shoreline miles that we report in our statistics include only the lake's exterior shoreline, and exclude the shorelines of islands located within a lake's boundaries. In lakes with many islands, those islands' combined shorelines may exceed a lake's exterior shoreline.

You can find many of the world's longest-shoreline lakes on Lakelubbers.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Surface Area | LakeLubbers

This is the area (acreage, square kilometers, etc.) of the top surface area of a lake - measured at a lake's normal elevation. The surface area can be considerably smaller or larger when lake levels are lower or higher than normal. North America's Lake Superior is the world's largest freshwater lake by this measure.

The other measure of a lake's size is the lake's water volume. By that measure, the world's largest freshwater lake is Lake Baikal in Siberia.

You can find many of the world's largest lakes (acres) on Lakelubbers. There is no widely-accepted minimum surface area that defines a lake. What Lakelubbers describes as a lake, you might call a pond. The smallest lake that Lakelubbers currently includes is Hawaii's 2-acre Lake Waiau.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Water Level Control | LakeLubbers

This is the organization that controls water releases or outflows from the lake or reservoir. In the USA, this is often the US Army Corps of Engineers, a power company, a municipal water system, an irrigation district, or a paper manufacturing company. In the case of private or gated lakes, a homeowners' association may be the lake's controlling authority.

Many lakes cross borders, including North America's Great Lakes. The control of such lakes and their coveted freshwater may be amicably shared - or hotly disputed.

"Water wars" continue at many lakes as growing populations and crop irrigation needs compete for the freshwater that lakes contain.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.

Lake Type | LakeLubbers

There are 3 basic types of lakes that are currently included on LakeLubbers. 2 types may be dammed or not dammed, producing 5 classifications.

- A Reservoir is a man-made freshwater lake that is usually created by damming rivers.

- A Natural Freshwater Lake occurs naturally - often by glacial activity - and has a salinity of less than 30 parts per thousand. It may be dammed to produce electricity or for other reasons.

- A Natural Saltwater Lake occurs naturally and has a salinity of more than 30 parts per thousand (ppt). It may be dammed.

"Brackish" water may be categorized as freshwater or saltwater, depending on its salt content (salinity). Oligohaline water has less than 15 ppt of salt. Mesohaline water has 15-29 ppt. Polyhaline has 30-335 ppt.


Lakes for Vacation and Recreation

Except as noted, Copyright © LakeLubbers LLC. All Rights Reserved.