Incahuasi Island is in the middle of the Salar de Uyuni salt flat in the Potosí Department in Bolivia. The island covers 24.62 hectares (60.8 acres) and consists of rocky, hilly terrain, with unusual and fragile coral-like structures and deposits that often consist of fossils and algae. It is the remains of the top of an ancient volcano which was submerged when the area was part of a giant prehistoric lake, roughly 40,000 years ago.Photo: Martin St-Amant