The northern edge of this 3000-square-kilometre basin covered by a vast crust of saline minerals lies some 10km south of San Pedro. The largest salt flat in Chile, SALAR DE ATACAMA is formed by waters flowing down from the Andes which, unable to escape from the basin, are forced to evaporate, leaving salt deposits on the earth. It’s not a dazzling white like the Salar de Surire, or Bolivia’s Salar de Uyuni, but it’s fascinating all the same – especially when you get out and take a close look at the crust, which looks like coffee-coloured coral reef, or ice shards, and clanks when you walk on it. The salar contains several small lakes, including Laguna Chaxa, home to dozens of flamingoes, and the beautiful Laguna Salada, whose waters are covered with floating plates of salt.
Many tour companies also take you for a float in the saline waters of Laguna Cejar, 19km from San Pedro. This emerald green lagoon contains even more salt than the Dead Sea. Your guide will warn you to wear shoes when walking on the banks, as very sharp salt crests can cut your feet. Remember to bring bottles of water to wash the salt off afterwards.