Lake Baikal’s maximum depth is 1,642 meters, the greatest reliably recorded depth for any lake.
Baikal lies in southern Siberia, Russia, within an active continental rift where the Earth’s crust is gradually pulling apart. The lake is about 25–30 million years old, making it one of the planet’s oldest lakes as well as its deepest. Its basin is divided into northern, central, and southern sections, with the central basin reaching the greatest depth.
Depth gives Baikal an extraordinary volume. Although it is only the world’s seventh-largest lake by surface area, it contains more freshwater than any other lake—about 22–23% of the world’s unfrozen fresh surface water. It holds more water than all the North American Great Lakes combined.
Baikal’s isolation and age have also produced exceptional biodiversity. Many species are endemic, including the Baikal seal, the only seal species living exclusively in freshwater. A frequent mistake is to confuse maximum depth with average depth: Baikal’s average depth is about 744 meters, while 1,642 meters refers to its deepest measured point.