The Uyuni salar

- by far the biggest salt lake in the world -

covers 12,000 square kilometers of the Bolivian Altiplano at an altitude of 3650 meters.

It was formed when the water of a huge lake covering a large part of the southerm Altiplano evaporated thousands of years ago leaving salt that had been driven into the lake by the water flowing from the surrounding mountains where it had been deposited millions of years ago before the Andes where formed, when the region was still beneath the ocean. The salt layers, sandwiched between sedimentary deposits, reach a depth of 120 meters. Every year, usually between December and March, during the rainy season, the salar is covered by water and, beneath the crust, salt always remains saturated with water. The strange polygonal figures of raised salt covering the surface of the salar in the dry season are formed when the upper layer od salt dries and contract, forming cracks drawing the underlying salty water up by capillarity.

It's better to take some precautions before venturing onto the salar: you need a good 4WD, food and water supply, and a well filled reservoir...

To continue the trip on the salar, click HERE