The 10 Largest Lakes in the World
Lakes are among Earth’s most important freshwater and saline systems. They regulate climate, store vast quantities of water, support fisheries, shape human settlement, and preserve ancient ecological histories. When scientists rank the largest lakes in the world, they usually do so by surface area, not volume or depth. This method highlights how much of the planet’s surface each lake occupies and how influential it is geographically and climatically.
Some of the world’s largest lakes are freshwater, others are saline, and one is technically a lake despite being salty enough to resemble an ocean. Together, these massive bodies of water influence weather patterns, biodiversity, trade routes, and human civilization on a continental scale.
1. Caspian Sea
The Caspian Sea is the largest lake in the world by surface area, covering approximately 371,000 square kilometers. Despite its name, it is not a sea but a landlocked lake with no natural outlet to the world’s oceans. Its waters are saline, though less salty than seawater.
Bordered by five countries, the Caspian Sea plays a major role in regional climate and economics. It supports valuable fisheries, including sturgeon that produce much of the world’s caviar. The lake also holds vast oil and gas reserves beneath its seabed, making it geopolitically significant. Over geological time, the Caspian Sea is a remnant of an ancient ocean that gradually became isolated as continents shifted.
2. Lake Superior
Lake Superior is the largest freshwater lake by surface area in the world, spanning about 82,100 square kilometers. It sits on the border between the United States and Canada and is the largest of North America’s Great Lakes.
Lake Superior contains roughly 10 percent of the world’s surface freshwater. Its waters are cold, deep, and exceptionally clear, giving it one of the longest water retention times of any lake. Storms on Lake Superior can generate waves comparable to those of the open ocean. Historically, it has been a major shipping route and remains vital to trade, ecology, and regional climate moderation.
3. Lake Victoria
Lake Victoria is Africa’s largest lake and the largest tropical lake in the world, covering around 68,870 square kilometers. It is shared by Tanzania, Uganda, and Kenya and serves as the primary source of the White Nile.
The lake supports tens of millions of people through fishing, transportation, and agriculture. Its ecosystem has undergone dramatic change due to introduced species, overfishing, and pollution. Despite these challenges, Lake Victoria remains one of the most important freshwater resources on Earth and a cornerstone of East African life and economy.
4. Lake Huron
Lake Huron covers approximately 59,600 square kilometers and is another of North America’s Great Lakes. It is connected to Lake Michigan through the Straits of Mackinac, forming a single hydrological system.
Lake Huron has the longest shoreline of any Great Lake, due to its many bays and islands. It supports diverse ecosystems, including wetlands and forests, and plays a critical role in freshwater biodiversity. Historically, it was a major route for Indigenous peoples and later European explorers and traders.
5. Lake Michigan
Lake Michigan is unique among the Great Lakes because it lies entirely within the United States. It covers about 58,000 square kilometers and supports major cities along its shores, including Chicago and Milwaukee.
The lake influences regional weather, often producing lake-effect snow in winter and moderating summer temperatures. It is a major source of drinking water and supports commercial shipping, recreation, and fisheries. Its size and economic importance make it one of the most influential freshwater lakes in the world.
6. Lake Tanganyika
Lake Tanganyika is the second-largest freshwater lake by volume and the longest freshwater lake in the world, stretching over 670 kilometers. Its surface area is approximately 32,900 square kilometers.
Located in the East African Rift Valley, the lake is extraordinarily deep and ancient, estimated to be 9–12 million years old. It contains hundreds of endemic species found nowhere else on Earth. Communities along its shores depend heavily on fishing, and its depth allows it to store immense quantities of freshwater despite its smaller surface area compared to other lakes.
7. Lake Baikal
Lake Baikal, located in Siberia, covers about 31,500 square kilometers but holds more freshwater than any other lake on Earth. It contains roughly 20 percent of the world’s unfrozen freshwater.
Baikal is the deepest and oldest freshwater lake, reaching depths of over 1,600 meters and an age of more than 25 million years. Its isolation has led to remarkable biodiversity, including species such as the Baikal seal. The lake is considered one of the most important freshwater ecosystems on the planet.
8. Great Bear Lake
Great Bear Lake is the largest lake entirely within Canada, covering around 31,000 square kilometers. It lies in the Northwest Territories, just south of the Arctic Circle.
The lake is extremely cold and remote, with ice covering its surface for much of the year. Its waters are among the cleanest and least polluted in the world. Great Bear Lake plays an important role in Indigenous culture and Arctic ecology, supporting fish species adapted to cold, pristine conditions.
9. Lake Malawi
Lake Malawi, also known as Lake Nyasa, covers approximately 29,600 square kilometers and lies within the East African Rift system. It is shared by Malawi, Mozambique, and Tanzania.
The lake is famous for its extraordinary diversity of cichlid fish, with more species than any other lake on Earth. It supports fisheries, tourism, and agriculture for millions of people. Like other rift lakes, its depth and clarity make it a crucial freshwater reservoir in a region sensitive to climate variability.
10. Great Slave Lake
Great Slave Lake covers about 28,600 square kilometers and is the deepest lake in North America. It lies in Canada’s Northwest Territories and plays a major role in regional hydrology.
The lake remains frozen for much of the year, but during summer it supports fishing, transportation, and wildlife. Its depth allows it to store large volumes of cold freshwater, and it has become increasingly important for climate research as northern regions warm rapidly.
Why the World’s Largest Lakes Matter
The largest lakes on Earth are more than geographic features. They regulate climate, store critical freshwater resources, support unique ecosystems, and sustain human populations across continents. Many are ancient, holding records of past climates and evolutionary history within their sediments.
As climate change accelerates, these lakes face rising temperatures, pollution, invasive species, and changing water levels. Protecting them is essential not only for biodiversity, but for food security, water supply, and regional stability.
