Baikal is an ancient lake with living geology and a rare ecosystem. Here, singing winter ice, crystal clarity, and depths comparable to mountain heights meet.

Geography and scale
The lake is about 636 km long, up to 79 km wide, and roughly 31,722 km² in area. That’s comparable to Belgium’s area, and its length is nearly the distance between Moscow and St. Petersburg.

Depth and volume
Maximum depth is 1,642 m, average about 744 m; the lakebed lies roughly 1.2 km below sea level (relative to surface elevation). Total volume is around 23,600 km³—more than all five North American Great Lakes combined.

Ice and clarity
In winter, visibility reaches up to 40 m, and ice usually lasts from January to May, thickening to 70–120 cm (over 150 cm in harsh winters). Kilometer-long cracks “sing” as they release stress, building dramatic pressure ridges.

Biodiversity and endemics
Over 3,700 species and subspecies are recorded, about 80% endemic. The Baikal seal is one of the few freshwater pinnipeds; sponges and tiny crustaceans filter the water, maintaining its clarity.

Hydrology
More than 330 rivers and streams flow in, and a single river flows out; full water renewal takes about 330 years. High oxygen levels persist even at great depths—unusual for such deep lakes.

Climate and waves
Mountain corridors generate strong winds that can raise waves up to 4–5 m. Conditions shift fast: calm can turn into a storm within hours.

Geology and seismicity
Baikal sits in a continental rift and is slowly widening by millimeters per year. The region is seismically active, with frequent microquakes and ongoing lakebed reshaping.

Records and comparisons
About one-fifth of the planet’s surface unfrozen freshwater is stored here. If Baikal’s water were spread over Germany, it would form a layer roughly 66 m deep. It amounts to around 3 million liters per person on Earth—more than decades of typical household use.

Notable numbers
Shoreline exceeds 2,100 km; there are about 27 islands. Summer surface temperatures are 8–12 °C (up to 20 °C in shallow bays); deep waters remain 3–4 °C year-round. Under-ice visibility reaches 40 m, and ice persists for 4–5 months.

Conservation
Baikal is sensitive to warming, pollution, and invasive species. Responsible tourism and scientific monitoring are essential to preserve its water clarity and unique biodiversity.