Salar de Uyuni is with its 12.000 kmē (7,456 sq. mi.) is the world's largest salt flat. It is located in Potosí department in southwest Bolivia, near the crest of the Andes, 3650 meters high (11975 ft.). The major minerals found in the salar are halite and gypsum. Uyuni is roughly 300 times the size of the better-known Bonneville Salt Flats in the United States.

Some 40,000 years ago, the area was part of Lake Minchin, a giant prehistoric lake. When the lake dried, it left behind two modern lakes, Poopó and Uru Uru, and two major salt deserts, Salar de Coipasa and the larger Uyuni.

Salar de Uyuni is estimated to contain 10 billion tons of salt of which less than 25,000 tons is extracted annually.

SALAR OF UYUNI