Lake Baikal in southeastern Siberia is the deepest lake on Earth at 1,642 meters, the oldest at approximately 25 million years, and holds roughly 20 percent of the world's unfrozen surface freshwater. If every other freshwater lake and river on Earth dried up, Baikal alone could supply the world's population with drinking water for roughly 40 years.
Overview
Lake Baikal is a superlative lake in every sense. Its maximum depth of 1,642 meters makes it deeper than most of the world's seas. Its volume of 23,615 cubic kilometers exceeds that of all five Great Lakes combined. And its age of approximately 25 million years makes it the oldest lake on Earth — most lakes last only 10,000 to 15,000 years before filling with sediment.
The lake sits in a continental rift zone where the Eurasian Plate is slowly pulling apart, deepening the basin by about 2 centimeters per year. This tectonic activity, combined with thick sediment layers on the lake floor (up to 7 kilometers deep), means the true depth of the Baikal rift approaches 9 kilometers — deeper than any ocean trench outside the Pacific.
Geography
- Surface Area: 31,722 km²
- Max Depth: 1,642 m
- Length: 636 km
- Volume: 23,615 km³ (20% of world's unfrozen freshwater)
Lake Baikal is crescent-shaped, stretching 636 kilometers from southwest to northeast in the Russian republic of Buryatia and Irkutsk Oblast. It averages 48 kilometers in width and is surrounded by mountain ranges on all sides — the Barguzin Range to the east, the Baikal Mountains to the northwest, and the Khamar-Daban Range to the south.
Over 330 rivers flow into Baikal, the largest being the Selenga River, which originates in Mongolia and provides about half of the lake's inflow. Remarkably, only one river flows out: the Angara, a tributary of the Yenisei that eventually reaches the Arctic Ocean. The lake contains 27 islands, the largest being Olkhon Island (730 square kilometers), which is home to roughly 1,500 permanent residents and is considered one of the most sacred sites in Siberian shamanism.
Baikal's water is exceptionally pure, with visibility reaching 40 meters in winter and spring. This clarity is largely maintained by billions of tiny crustaceans called Epischura baikalensis, an endemic copepod that filters the entire volume of the lake's upper waters roughly three times per year.
Wildlife
- Endemic Species: Over 2,500 (found nowhere else)
- Iconic Species: Baikal seal (nerpa), omul fish, Epischura copepod
- Fish Species: Over 60 (75% endemic)
Lake Baikal is often called the "Galapagos of Russia" due to its extraordinary endemism. Over 2,500 species of plants and animals found in and around the lake exist nowhere else on Earth. The Baikal seal, or nerpa, is the world's only exclusively freshwater seal species, with a population of roughly 80,000-100,000. Scientists believe the nerpa's ancestors migrated from the Arctic Ocean via river systems millions of years ago.
The lake is home to over 60 fish species, including the prized omul (a relative of salmon) and the bizarre golomyanka, a translucent fish that lives at depths of up to 1,600 meters, gives birth to live young, and is so oily that it was historically used as lamp fuel by local Buryat people. The golomyanka is so transparent that you can read newspaper print through its body.
Key Facts
- Lake Baikal is the deepest lake in the world at 1,642 meters.
- It is the oldest lake on Earth at approximately 25 million years.
- Baikal holds 23,615 km³ of water — 20% of the world's unfrozen surface freshwater.
- Over 2,500 species found in Lake Baikal exist nowhere else on the planet.
- The lake was designated a UNESCO World Heritage Site in 1996.
Fun Facts
- If you emptied Lake Baikal and refilled it using every river on Earth, it would take roughly one year to fill.
- In winter, Baikal's ice is so clear and thick (up to 2 meters) that vehicles can drive across it — an official ice road operates for several months each year.
- The lake experiences over 2,000 minor earthquakes per year due to its active rift zone.
- The golomyanka fish is so oily that if left in the sun, it literally melts into a pool of fat, leaving only bones behind.
Final Thoughts
Lake Baikal is a natural wonder without equal — the deepest, oldest, and most voluminous freshwater lake on Earth, harboring an evolutionary treasury of endemic species that has been accumulating for 25 million years. Protecting this irreplaceable body of water from industrial pollution, tourism pressures, and climate change is not merely a Russian concern but a global responsibility.
