10 Ancient Lakes That Still Exist on Earth Today

Ancient lakes are lakes that have consistently carried water for more than one million years. These lakes continue to persist because of the plate tectonics in an active rift zone creates extremely deep lakes and difficult to fill with sediment naturally.

So here is the list of 10 Ancient Lakes That Still Exist on Earth Today:

1. Lake Baikal, Russia

There are few reasons that make Lake Baikal as one of the most notable lakes in the world:

- Lake Baikal was formed as an ancient rift valley by the Baikal Rift Zone 25–30 million years ago, makes it the oldest lake in the world today,

- Lake Baikal has the typical crescent shape with a surface area of 12,248 square miles (31,722 km²),

- Lake Baikal is the clearest and the largest freshwater lake by volume which contains 22–23% of the fresh surface water on earth,

- Lake Baikal is the deepest lake with a maximum depth of 1,642 meters,

- Lake Baikal contains 27 islands; with the largest is Olkhon (45 miles long). Olkhon is the third-largest lake-bound island in the world.

- Lake Baikal was declared as World Heritage Site by UNESCO in 1996.

2. Lake Zaysan, Kazakhstan

Lake Zaysan. Photo by Dmitry A. Mottl. CC by 3.0

Lake Zaysan is considered to be even older than Lake Baikal, at least 65 million years old. But its exact age is labelled with some uncertainty. Some geological studies of the Zaysan basin have been reviewed, but it is still difficult to find the direct indication of its age.

Lake Zaysan is a freshwater lake with a surface area of 700 square miles (1,810 km²), which makes it the largest lake in the East Kazakhstan Region. It has a maximum depth of 15 meters, but the lake has risen 6 meters above its natural level since the construction of the Bukhtarma dam on the Irtysh downstream from the Zaysan.

3. Lake Maracaibo, Venezuela

Lake Maracaibo is one of the oldest lakes on Earth at 20–36 million years old, and was once the largest lake in South America at 5,100 square miles (13,210 km²). The geological record shows that it has been a true lake in the past, but now it is considered a large brackish tidal bay that is connected to the Gulf of Venezuela by Tablazo Strait.

Alonso de Ojeda was the first European to discover the bay in 1499, on a voyage with Amerigo Vespucci. According to legend, Ojeda's expedition found groups of indigenous stilt houses built on water. These stilt houses reminded Vespucci of the city of Venice, so he named the region Venezuela (which in Spanish means little Venice).

4. Lake Tanganyika, East Africa

Lake Tanganyika. Photo: www.zambiatourism.com

Lake Tanganyika is the ancient freshwater lake with its three basins are of different ages. The central has been estimated around 9-12 million years, the northern 7-8 million years, and the southern 2-4 million years old. One of the river flowing into the lake is Malagarasi river which enters the east side of Lake Tanganyika. The Malagarasi river is older than Lake Tanganyika.

Lake Tanganyika is the largest rift valley lake in Africa with a surface area of 12,700 square miles (32,900 km²). The lake is divided among four countries: Burundi, Democratic Republic of the Congo, Tanzania, and Zambia. Lake Tanganyika is also the second largest lake by volume in the world after Lake Baikal in Siberia.

5. Lake Malawi, East Africa

Lake Malawi. Photo by Noel Peries, via www.maggieinafrica.com

Lake Malawi, also known as Lake Nyasa or Lago Niassa, is the major meromictic lake which has a total surface area of around 11,400 square miles (29,600 km²). Meromictic lake means that its water layers do not mix. The permanent stratification of the water and the oxic-anoxic boundary relating to oxygen in the water are maintained by moderately thermal gradients and small chemical.

Ancient Lake Malawi has been tipically estimated to be 1-2 million years old which formed by a divergent plate tectonics boundary. However, the recent evidence has been estimated that the basin started to form about 8.6 million years ago and deep-water condition first occurred 4.5 million years ago.

6. Caspian Sea, Eurasia

Caspian Sea. Photo: via wikipedia.org

The Caspian Sea, located between Europe and Asia, is generally regarded as the largest inland endorheic salt lake. However, the ancient inhabitants always regarded Caspian as a sea because of its large size and saltiness.

Caspian sea has a surface area of around 143,200 square miles (371,000 km²), and a volume of 78,200 km³. It also has a salinity of about one third of the salinity of most oceans, approximately 1.2%. Though today the Caspian Sea is a freshwater lake in its northern portions due to the current inflow of fresh water.

The Caspian Sea, is believed to be one of the remnants of the ancient Paratethys Sea. The other remnants are Black Sea, Lake Urmia, and Namak Lake. About 5.5 million years ago, Caspian Sea became landlocked because of the tectonic movement and a fall in sea level.

7. Lake Ohrid, Balkans

Lake Ohrid. Photo by: Dave Proffer on Flickr, CC by 3.0

Lake Ohrid has been estimated to be around five million years old, and belongs to a group of Dessaret basins that originated from a geotectonic depression during the Pliocene epoch. However, Macedonian media reported in 2008 that international experts will be researching the lake to determine its age.

Lake Ohrid is the deepest lake of the Balkans with a maximum depth of 288 meters, and covers an area of 358 square kilometers. It is located between southwestern Macedonia and eastern Albania. Around two thirds part of the lake belongs to the Republic of Macedonia, and the rest belongs to Albania.

In 1979, UNESCO declared Lake Ohrid as a World Heritage Site. In 2010, NASA decided to name a hydrocarbon lake on the Saturnian moon Titan after Lake Ohrid: Ohrid Lacus. And in 2014, UNESCO added the Ohrid-Prespa Transboundary Reserve between Albania and Macedonia to UNESCO's World Network of Biosphere Reserves.

8. Lake Biwa, Japan

Lake Biwa is the largest freshwater ancient lake in Japan with the surface area of  258.8 square miles (670.3 km²). It is also one of the oldest lake in the world dating to around 4 million years ago. According to Naturalists, Lake Biwa is of tectonic origin which houses over 1000 species and subspecies, including around 60 endemic.

Lake Biwa, which formerly known as the Awaumi (Freshwater Sea), also houses an important archaeological site of Jōmon period that goes back to the beginning of the Initial Jōmon period (ca. 9300 BP). The site lies at a depth of 2m to 3m from the bottom, near the southern end of Lake Biwa.

9. Lake Lanao, Philippines 

Lake Lanao. Photo: lanaodelsur.gov.ph

Lake Lanao is the second largest lake in the Philippines with a surface area of 130 square miles (340 km²). This rift lake is counted as one of the 15 ancient lakes in the world, which was formed by the collapse of a large volcano and the tectonic-volcanic damming of a basin between two mountain ranges.

There is a myth among the Meranaw tribe that describes the formation of Lake Lanao. The myth said that a group of angels created the hole in order to removed the vast population of Mantapoli. The hole was filled with water and threatened to drown the rest of the world. To prevent this, the angels asked the help of the Four Winds to gouge out an outlet. The hole then formed into Lake Lanao and the outlet formed into the Agus river.

10. Lake Titicaca, South America

Lake Titicaca is a large mountain lake that covers area of 3,232 square miles (8,372 km²). It is the largest lake in South America by surface area and by volume of water. Note that although Lake Maracaibo has a larger surface area, but now it is considered as a tidal bay, not a lake.

Lake Titicaca has a surface elevation of 3,812 meters and is often called the "highest navigable lake" in the world. However, its water level dropped constantly since the 2000 caused by the shortened rainy seasons, and its biodiversity is threatened by water pollution. Thus in 2012, the Global Nature Fund nominated the lake as "Threatened Lake of the Year".