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.

A Rafale fighter jet flies over France's Charles de Gaulle aircraft carrier as it makes its way in the Gulf, January 28, 2016. (Photo by Philippe Wojazer/Reuters)

An environmental activist performs during a protest in front of the headquarters of Brazilian mining company Vale SA in downtown Rio de Janeiro, Brazil, November 16, 2015. The collapse of two dams at a Brazilian mine, owned by Vale SA and BHP Billiton Ltd, has cut off drinking water for quarter of a million people and saturated waterways downstream with dense orange sediment that could wreck the ecosystem for years to come. Nine people were killed, 19 are still listed as missing and 500 people were displaced from their homes when the dams burst at an iron ore mine in southeastern Brazil on November 5. (Photo by Sergio Moraes/Reuters)

A child dressed as a clown takes part in the celebration of the Virgen de los Desamparados, or Our Lady of the Abandoned, at Diria town, Nicaragua May 14, 2016. (Photo by Oswaldo Rivas/Reuters)

View of Evolutions installation by artist Yann Nguema at the Saint-Jean Cathedral during the rehearsal for the Festival of Lights (Fetes des Lumieres) in Central Lyon, France, late December 7, 2016. (Photo by Emmanuel Foudrot/Reuters)

Cycling jerseys, part of a collection belonging to French cycling fan Gerald, hang from a line during the 4th stage of the Tour de France cycling race from Seraing in Belgium to Cambrai in France, July 7, 2015. Photographing the Tour de France cycling race comes with highs and lows: the buzz from capturing just the right image, the tedium of long journeys, the painstaking set-up of equipment, the breath-taking scenery. Reuters photographers have worked not only to capture the thrills and spills on the roads and mountain passes. They have also shot a set of pictures showing their own quirky view from behind the scenes as they travelled through the Netherlands, Belgium and France. (Photo by Eric Gaillard/Reuters)

A man pours red wine on a girl's head during the Batalla del Vino (Battle of Wine) in Haro, on June 29, 2015. Every year thousands of locals and tourists climb a mountain in the northern Spanish province of La Rioja to celebrate St. Peter's day covering each other in red wine while tanker trucks filled with wine distribute the alcoholic beverage to water pistols, back mounted spraying devices, buckets which are randomly poured on heads and into any other available container. More than nine thousand people threw around 130,000 litres of wine during this year's Haro Wine Festival, according to local media. (Photo by Cesar Manso/AFP Photo)

If the most popular foods of Rio de Janeiro have one thing in common, it is their informality. You can find fine restaurants in the city, but they do not set Rio apart from other places. What does set it apart, and what invariably brings its residents, known as "Cariocas," together is the unpretentious food they eat in bright, loud, crowded bars and restaurants, on busy street corners, or after a day at the beach. Here: A view of traditional bolinhos de bacalhau (fried codfish balls) in Rio de Janeiro, Brazil, May 7, 2016. (Photo by Sergio Moraes/Reuters)