Salar de Uyuni (World's Largest Mirror), Andes in Southwest Bolivia

Salar de Uyuni or Salar de Tunupa is the world's largest salt flat, at 10,582 square kilometers (4,086 sq mi). It is in the Daniel Campos Province in Potosí in southwest Bolivia, near the crest of the Andes and is at an elevation of 3,656 meters (11,995 ft) above sea level.

The Salar was formed as a result of transformations between several prehistoric lakes. It is covered by a few meters of salt crust, which has an extraordinary flatness with the average elevation variations within one meter over the entire area of the Salar. 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. The large area, clear skies, and exceptional flatness of the surface make the Salar an ideal object for calibrating the altimeters of Earth observation satellites. Following rain, a thin layer of dead calm water transforms the flat into the world's largest mirror, 129 kilometers (80 miles) across. 

The Salar serves as the major transport route across the Bolivian Altiplano and is a major breeding ground for several species of flamingos. Salar de Uyuni is also a climatologist transitional zone since the towering tropical cumulus congest us and cumulonimbus incus clouds that form in the eastern part of the salt flat during the summer cannot permeate beyond its drier western edges, near the Chilean border and the Atacama Desert.

 

Salar is salt flat in Spanish. Uyuni originates from the Aymara language and means a pen (enclosure); Uyuni is a surname and the name of a town that serves as a gateway for tourists visiting the Salar. Thus Salar de Uyuni can be loosely translated as a salt flat with enclosures, the latter possibly referring to the "islands" of the Salar; or as "salt-flat at Uyuni

 

 

 

 

Salar de Uyuni is part of the Altiplano of Bolivia in South America. The Altiplano is a high plateau, which was formed during uplift of the Andes mountains. The plateau includes fresh and saltwater lakes as well as salt flats and is surrounded by mountains with no drainage outlets. The Salar contains a large amount of sodium, potassium, lithium and magnesium as well as borax. Of those, lithium is arguably most important as it is a vital component of many electric batteries. With estimated 9,000,000. The Bolivia holds about 43 % of the world's known lithium reserves; most of those are in the Salar de Uyuni

The area has a relatively stable average temperature with a peak at 21 °C in November to January and a low of 13 °C in June. The nights are cold all through the year, with temperatures between −9 °C and 5 °C. The relative humidity is rather low and constant throughout the year at 30% to 45%. The rainfall is also low at 1 mm to 3 mm per month between April and November, but it may increase up to 80 mm in January. However, except for January, even in the rainy season the number of rainy days is fewer than 5 per month and Every November, Salar de Uyuni is the breeding ground for three species of pink South American flamingo: the Chilean, Andean, and rare James's flamingos, their color presumably originating from feeding on pink algae. About 80 other bird species are present, including the horned coot, Andean goose, and Andean hillstar. The Andean fox, or culpeo, is also present, and islands in the Salar host colonies of rabbit-like viscachas

Salar de Uyuni attracts tourists from around the world. As it is far from the cities, a number of hotels have been built in the area. Due to lack of conventional construction materials, many of them are almost entirely (walls, roof, furniture) built with salt blocks cut from the Salar. The first such hotel, named Palacio de Sal, was erected in 1993–1995 in the middle of the salt flat, and soon became a popular tourist destination. However, its location in the center of a desert caused sanitation problems, as most waste had to be collected manually. Mismanagement caused serious environmental pollution and the hotel had to be dismantled in 2002. One major tourist attraction is an antique train cemetery. It is 3 km outside Uyuni and is connected to it by the old train tracks. The town served in the past as a distribution hub for the trains carrying minerals en route to Pacific Ocean ports. The rail lines were built by British engineers arriving near the end of the 19th century and formed a sizeable community in Uyuni. The engineers were invited by the British-sponsored Antofagasta and Bolivia Railway Companies, now Ferrocarril de Antofagasta a Bolivia. The rail construction started in 1888 and ended in 1892. It was encouraged by Bolivian President Aniceto Arce, who believed Bolivia would flourish with a good transport system, but it was also constantly sabotaged by the local Aymara indigenous Indians who saw it as an intrusion into their lives. The trains were mostly used by the mining companies. In the 1940s, the mining industry collapsed, partly because of mineral depletion. Many trains were abandoned, producing the train cemetery. There are proposals to build a museum from the cemetery.