Salar de Uyuni (or Salar de Tunupa)[1] is the world's largest salt flat. It is over 10,000 square kilometres (3,900 sq mi) in area.[2]
It is in Potosí in southwest Bolivia, near the crest of the Andes at an height of 3,656 metres (11,995 ft) above sea level.[3]
The crust serves as a source of salt and covers a pool of brine, which is exceptionally rich in lithium. It contains 50% to 70% of the world's known lithium reserves.[4] The large area, clear skies, and exceptional flatness of the surface make the Salar ideal for calibrating the altimeters of Earth observation satellites.[5][6]