What is the largest freshwater lake by volume?

Lake Baikal is the largest freshwater lake in the world by volume. Located in southern Siberia, Russia, it contains roughly 22–23% of the planet’s unfrozen surface freshwater—more than all five North American Great Lakes combined.

Baikal’s enormous volume is explained mainly by its exceptional depth. It reaches about 1,642 metres, making it the deepest lake on Earth. Although its surface area is smaller than Lake Superior’s, its deep rift-valley basin stores far more water. The lake formed in an active continental rift where Earth’s crust is slowly pulling apart.

Baikal is also one of the world’s oldest lakes, estimated to be about 25–30 million years old. Its long geological history has allowed many distinctive species to evolve, including the Baikal seal, the only seal species found exclusively in freshwater. Lake Tanganyika is the second-deepest lake and also holds enormous freshwater reserves, while Lake Superior is the largest freshwater lake by surface area.