A French farmer leads her cow through the livestock area as preparations continue on the eve of the opening of the International Agricultural Show in Paris, France, February 26, 2016. The Paris Farm Show runs from February 27 to March 6, 2016. (Photo by Benoit Tessier/Reuters)

A model presents a creation by Australian designers Tamara Ralph and Michael Russo as part of their Haute Couture Spring/Summer 2017 fashion show for Ralph & Russo in Paris, France January 23, 2017. (Photo by Gonzalo Fuentes/Reuters)

Two girls wearing traditional Sevillian dresses talk during the “Feria de Abril” (April Fair) in Sevilla on April 30, 2017. The fair dates back to 1847 when it was originally organized as a livestock fair but has turned into a week of flamenco dancing, music and bullfighting. (Photo by Cristina Quicler/AFP Photo)

View of a light show on the city's iconic Arc de Triomphe monument during the New Year celebration in Paris, France, December 31, 2016. (Photo by Jacky Naegelen/Reuters)

Girls watch a procession during the “Fiesta de las Palancas” celebration to ask for blessings and abundance during the new year in Panchimalco, El Salvador, January 5, 2017. (Photo by Jose Cabezas/Reuters)

A dog snuggles up to a potential owner on the opening day of Dog Cafe, a coffee shop where people can adopt shelter dogs in Los Angeles, California, United States, April 7, 2016. (Photo by Lucy Nicholson/Reuters)

Maria, 18, wearing a traditional Sevillana outfit, poses for a portrait during the traditional Feria de Abril (April fair) in the Andalusian capital of Seville April 16, 2013. (Photo by Marcelo del Pozo/Reuters)

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 located in the Potosí and Oruro departments in southwest Bolivia, near the crest of the Andes, and is elevated 3,656 meters (11,995 ft) above mean 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 altitude variations within one meter over the entire area of the Salar.