Lake Baikal is a rift lake in Russia, located in southern Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast. It is the largest freshwater lake by volume in the world, containing roughly 20% of the world's unfrozen surface fresh water. With 23,615.39 km3 (5,700 cu mi) of fresh water and a maximum depth of 1,642 m (5,387 ft), Baikal is the world's deepest lake. It is considered among the world's clearest lakes and is considered the world's oldest lake — at 25 million years. It is the seventh-largest lake in the world by surface area.
Ice on Baikal is there till May. But in April no one drives on it. The ice thickness of Lake Baikal surface reaches 1,5-2 meters. These ice has different patterns in different parts of the lake. It happens because water is freezing layer by layer. Especially it is very interesting to find a fish or a branch in the ice. The ice in Baikal is the most transparent in the world! And this is true. You can see everything till the bottom: fish, green stones, plants and bluish gulf. The water in the lake is so clear, that you can see various objects on the depth of 40 meters.