The biggest lake in the world can be classified in a number of different ways. I have chosen to classify the biggest lake according to the amount of water it contains, but will make honorable mention extremely large lakes by square kilometerage.

The biggest lake, by volume, in the world is Lake Baikal in Russia at almost 24,000 cubic kilometers. It contains 20% of the world’s supply of fresh water and has more water than all of the Great Lakes of North American combined! It can reach depths of almost 1700 m at points and has been declared a UNESCO World Heritage Site.

The Caspian Sea is the biggest body of water inland by square kilometers; however, with a salinity of about one third of sea water, some think of it, well, as a sea. It has 78,000 cubic kilometers of water.

The biggest, completely fresh water lake in the world is Lake Tanganyika in Africa at almost 19,000 cubic kilometers. This lake is so large that it borders four countries: Burundi, Democratic Republic of the Congo, Tanzania and Zambia.

Both Lake Baikal and Lake Tanganyika were formed in rift valleys and therefore both are long and crescent shaped. A rift valley is a geological lowland, that has been created by the Earth’s shifting plates; in essence, a place where the Earth is opening up. Many of the world’s rift valleys contain lakes similar to Lake Baikal and Lake Tanganyika. Lake Superior in North America sits in a midcontinental rift valley, and two lakes lie within another rift valley in Ontario, Canada.

Some of the world’s largest lakes by surface area are Lake Victoria (almost 69,000 square kilometers), Lake Huron (almost 60,000 square kilometers) and Lake Michigan (almost 58,000 square kilometers).