Lake Baikal, Russia

One of the world’s great natural wonders, Lake Baikal is an immense, crescent-shaped chasm in the earth, nearly 640 kilometers long and up to 80 kilometers wide. Situated in Russia’s great Siberian wilderness, its record-breaking size is matched only by its remoteness; the lake is 3200 kilometers west of the Pacific, 5100 kilometers east of Moscow, and roughly 200 kilometres north of the Mongolian border.

In winter Baikal’s entire surface freezes solid, and the super-cooled skin endures for over four months. Ice starts to form in early January, and doesn’t begin to break up until May. The ice becomes so thick that locals use it as a highway, nonchalantly driving their Ladas and husky teams across it as if it were terra firma. In fact, the lake’s icy crust is so thick that a temporary railroad was once laid over it during the 1904-5 Russo-Japanese War.