Salar de Uyuni
This MODIS Terra image from October 19, 2006, shows Salar de Uyuni, in Bolivia, in South America. Salar de Uyuni is the world's largest salt flat, at larger than 3000 square miles in size. It is located near the crest of the Andes mountains, at an altitute of 3650 meters!
This salt flat was once part of a giant prehistoric lake, that dried up, leaving behind 2 salt flats and two smaller lakes. It is estimated that Salar de Uyuni contains 10 billion tons of salt; its mineral content is mainly gypsum and halite.