• 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.
• Lake Baikal is the largest freshwater lake by volume in the world, containing roughly 20% of the world’s unfrozen surface fresh water.
• it contains more water than the North American Great Lakes combined.
• Baikal is the world’s deepest lake. 
• It is considered among the world’s cleares 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.
• Lake Baikal was formed as an ancient rift valley, having the typical long crescent shape.
• The lake was declared a UNESCO World Heritage Site in 1996.

Source: Wiki