Salar de Uyuni, Bolivia
The Salar was produced by transitions between numerous prehistoric lakes that existed around forty thousand years ago but had all evaporated over time. It is presently covered by a few meters of salt crust, which has an unusual flatness with average height fluctuations of less than one meter over the whole Salar. The crust provides salt and protects a pool of brine that is extremely rich in lithium. The Salar is perfect for calibrating the altimeters of Earth observation satellites due to its enormous size, bright sky, and unusual flatness of the land.
The Salar is an important trade route through the Bolivian Altiplano and a popular nesting habitat for various flamingo species. Salar de Uyuni is also a climatological transition zone, since the towering tropical cumulus congestus and cumulonimbus incus clouds that form in the salt flat's eastern part during the summer are unable to penetrate beyond its drier western margins, near the Chilean border and the Atacama Desert. Because Salar de Uyuni is a famous tourist attraction, a number of hotels have been developed in the vicinity. Due to a scarcity of conventional building materials, many of them (walls, roof, furnishings) are nearly entirely made of salt blocks harvested from the Salar.
An antique train graveyard is a popular tourist attraction. It is located 3 kilometers (1.9 miles) outside of Uyuni and is connected by ancient railroad tracks. In the past, the town acted as a distribution point for trains delivering minerals to Pacific Ocean ports. British engineers arrived at the end of the nineteenth century and developed the rail lines, forming a sizable colony in Uyuni.
