Uvs

Uvs Lake is what remains of a vanished sea. This shallow, hypersaline body of water—Mongolia's largest by surface area at 3,350 square kilometers—occupies a basin that once held a much larger water body thousands of years ago. The name derives from "subsen," referring to the bitter residue left when making fermented mare's milk. The lake has no outlet; everything that flows in either evaporates or concentrates into the brine that gives Uvs its distinctive character.

UNESCO recognized the Uvs Lake Basin as a World Heritage Site in 2003, following its designation as a Biosphere Reserve in 1997. The site represents something geographically extraordinary: where the world's most northern desert meets the Northern Hemisphere's southernmost tundra. This collision of biomes creates temperature swings from -58°C in winter to +47°C in summer—a 105-degree range that few ecosystems on Earth experience.

The basin also preserves human history. Over 40,000 archaeological sites document the succession of nomadic peoples—Scythians, Turks, Huns—who used this depression as a corridor between the Siberian taiga and Central Asian steppe. The province sits in the Great Lakes Depression, a tectonic hollow exceeding 100,000 square kilometers that includes Mongolia's other large western lakes.

The capital Ulaangom, 1,336 kilometers from Ulaanbaatar, remains isolated—no paved road connects it to the rest of the country. By 2026, Uvs will continue as a remote preserve where climate extremes and geographic isolation protect what connection would destroy.