The Ultimate Lake Baikal Quiz

Lake Baikal maxes out at about 1 mile in depth (slightly more than 1.6 kilometers).

No one is exactly sure how long Lake Baikal's been around, but it's estimated to be at least 25 million years old, and some high-end estimates range up to 50 million years old. That's even more impressive when you figure most freshwater lakes on Earth aren't more than about 20,000 years old.

The continental rift Lake Baikal is located in is one of the deepest actively spreading rifts on Earth. Given a great deal of time, it could even tear Asia apart.

There are about 5,500 cubic miles (23,000 cubic kilometers) of water in Lake Baikal -- nearly the same amount as in all the Great Lakes combined.

Long and narrow in shape, Lake Baikal has about 1,300 miles (2,100 kilometers) of shoreline.

More than 300 tributaries contribute water to Lake Baikal's water supply, although it's drained through only a single source: the Angara River.

More than a thousand species are unique to Lake Baikal and live nowhere else in the world, making it a major biodiversity hotspot. This includes the planet's only species of exclusively freshwater seals.

Golomyanka, the most common fish in Lake Baikal, melt into a puddle of fatty oil and bones if exposed to sunlight or warm temperatures. Their high fat content, however, along with their porous bone structure and lack of a swim bladder, make them adept at traversing the lake's vertical water column and extreme pressure differentials.

It’s thought that methane gas emissions cause the large circles on the ice of Lake Baikal, patterns often spotted by astronauts and satellites. The gas warms the water, causing it to rise. When the water then begins to rotate because of the Coriolis effect, it melts the ice in a vast ring shape.

The Baikalsk Pulp and Paper Mill first started operating in 1966, despite a large public outcry. Scientists and environmentalists are still concerned with the decades-long effect of the mill’s pollutants (as well as other industry and human pollutants) on the lake’s unique ecosystem. The effects of climate change are also a major worry.