These oldest lakes in the world include; Zaysan, Vostok, Lake Baikal, Lake Tanganyika and Lake Ohrid which carry important genetic and geological information about Earth. Many of them can be tens of millions of years old and support plant and animal life not seen anyplace else. Lake Baikal in Russia is the world’s deepest and holds 20% of the global unfrozen fresh water. Africa’s Lake Tanganyika is the second deepest one and famous for its cichlid fish species. Ohrid Lake that is found in North Macedonia and Albania is also famous for its rich stock of endemism. These lakes are topical for both public interest and scientific research because they are on the cradle for evolution, climate change, and ecosystems and therefore their preservation is paramount.
Zaysan
Lake Zaysan, located in Kazakhstan, is one of Asia’s oldest lakes and is fed by the Black Irtysh River. It supports a thriving fishing industry and lies in a semi-arid region surrounded by scenic landscapes. During the winter months, the lake freezes, with a maximum depth of 15 meters. The area boasts rich biodiversity and is crucial for regional water supply. Interestingly, Lake Zaysan has been a significant natural resource for thousands of years, providing sustenance and resources to the local communities.
Country: Kazakhstan, Uzbekistan, Age: 65 – 70 million years
Baikal
Lake Baikal, situated in Siberia, Russia, holds the title of the world’s deepest freshwater lake, with a depth reaching 1,642 meters (5,387 feet). It contains about 20% of the globe’s unfrozen freshwater. This ancient lake, over 25 million years old, is home to the unique Baikal seal and more than 1,700 plant and animal species, many of which are endemic. Each winter, Lake Baikal freezes entirely, with ice thick enough to support vehicles, while its exceptionally clear waters allow visibility up to 40 meters.
The lake features 27 islands, the largest being Olkhon, and is recognized as a UNESCO World Heritage Site. It is fed by 336 rivers and streams, with the Angara River as its only outflow. Lake Baikal is a popular spot for ice-diving and holds cultural significance for the local Buryat people. Despite its natural beauty, the lake is experiencing rapid warming due to climate change. Surrounded by picturesque mountains, Lake Baikal has inspired countless legends and stories over the years.
Country: Russia, Age: 25-30 million years
Issyk-Kul
Issyk-Kul Lake, located in the Kyrgyz Republic, is ranked among the largest and deepest in the world. It has been described as a salty lake, and its saltiness remains present even within its mountainous environment. The lake covers about 6,236 square kilometers (2,408 square miles) and reaches as deep as 668 meters (2,192 feet), making it one of the largest saline lakes by volume in the world.
Issyk-Kul, which in Kyrgyz means “warm lake,” does not freeze over during the winter seasons because of its salinity and depth. The lake is a vital natural resource of the region, hosting many flora and fauna species that are endemic to the region. Several health resorts and spas are found on the shores of the lake and make use of the mineral-rich waters of the lake for therapeutic treatments.
The region around Issyk-Kul is very saturated with historical and cultural riches, including archaeological sites and rock carvings. It’s also an important element in regional tourism, attracting people simply because of its beauty as well as opportunities for leisure and recreation.
Country: Kazakhstan, Age: 25 million years
Maracaibo
Located in Venezuela and connected to the Caribbean Sea, Lake Maracaibo is one of the world’s oldest lakes, renowned for its rich petroleum reserves and the Catatumbo lightning phenomenon, which occurs over 200 nights per year. The lake supports diverse bird species and is surrounded by fertile agricultural land, though oil extraction has led to significant pollution. The basin, inhabited for millennia, stands as a testament to the region’s historical and ecological significance.
Country: Venezuela, Age: over 20+ million years
Vostok
Vostok Subglacial Lake underneath Russia’s Vostok Station in Antarctica is the largest of subglacial lakes. It was found by Soviet Antarctic Expeditions in in 1993, by satellite altimetry; it is between 15-25 Million years old and is situated at 4000 meters depth under the ice.
In 2012 through drilling Russian scientists got to the surface and collected water samples of the lake in its frozen state. According to the research conducted the lake is as large as 250 kilometers in length, 50 kilometers in width, and has a maximum depth of 900 meters. The water has been isolated for millions of years, making it a Martian-point for analysis of ancient climate conditions and perhaps microbial survival. The interest in organisms from such extreme environment arises due to Lake Vostok being isolated for millions of years.
Country: Antarctica, Age: 15+ million years
Biwa
Lake Biwa is Japan’s largest freshwater lake, located in Shiga Prefecture near Kyoto. It is 4 million years old and therefore one of the world’s oldest lakes, with water supply for 15 million people. The lake has been identified as a biodiversity hotspot due to the presence of several endemic species, and it has also been declared a UNESCO Ramsar Wetland. Aquaculture is rather wide-ranging here, including carp and trout, and there are plenty of cultural and historical sites around the lake.
Lake Biwa is very famous for water sports and fishing. It is named after its resemblance to the name of an old Japanese lute called biwa. Lake Biwa is also one important migratory stopover for water birds; however, it has just one outlet of water- the Seta River towards Yodo River. Despite facing all the challenges of urbanization and pollution, Lake Biwa is revered in so many poems and stories of Japan. The rare mollusks and fish exist here, and seasonal festivals have cultural significance. Chikubu Island is one of the beautiful islands that tourists visit, and the surrounding environment of this lake falls within the Biwako Quasi-National Park. Flood control and water management require its waters significantly. There is conservation efforts to preserve the special environment around it.
Country: Japan, Age: 5-6 million years
Caspian Sea
It is the world’s largest inland water body – sea encased by five countries including Russia, Kazakhstan, Turkmenistan, Iran and Azerbaijan. Considered both a sea and a lake with an area of 371,000 sq km it has both freshwater and brackish water layers. The largest contribution it receives is from the Volga River. The Caspian Sea region is oil and natural gas assets, and contains many endemics such as Caspian seal, and significant commercial species like Caspian sturgeon relevant to the caviar trade. Over 400 fish species are found in the area which makes it a conservation significance zone.
The sea having no outlet is variable and its heights depend onclimate and anthropogenic impacts. The Caspian Sea has had for many years significant importance to trade and intercultural relations, though at present, it faces problems of polluting and overfishing. It has desert, mountainous and Steppe land and the major cities of the region such as Baku, the capital of Azerbaijan and Astrakhan, Russia. Caspian Sea is critical in energy transit and the legal status of which influences the distribution of resources. Beloved by ancient people as sanctified, it is an important stopover for migratory birds up to the present time.
Country: Azerbaijan, Iran, Kazakhstan, Russian Federation, Turkmenistan, Age: 5.5 million years.
Eyre (Kati Thanda-Lake Eyre)
Lake Eyre, Australia’s largest salt lake, is located in South Australia and lies 15 meters below sea level. This expansive basin, named after explorer Edward John Eyre, is usually dry, transforming into a vast salt flat. During rare floods, the lake fills up, becoming the country’s largest lake, attracting a variety of birdlife such as pelicans, gulls, and terns. These flood periods bring the area to life, offering a unique and dynamic ecosystem.
Country: Australia, Age: 5 million years
