One of the most striking geological wonders Bolivia offers is the Uyuni Salt Flats. This child of prehistoric lakes, with its peaks of ancient submerged volcanoes referred to as ‘islands’ and carved by erosion into a delicate filigree, its brine lake under a salt crust, picturesque lagoons where flamingos breed, and giant cacti, deserves a spot on the list. During the rainy season, a light layer of water converts it into a giant mirror, and it’s expanse and flatness makes it more preferable for calibrating satellites than the oceans. Multi-day tours of Uyuni don’t only include the world’s largest salt flats themselves, but also the surreal surrounding landscape, marked by gigantic cacti, red and green lagoons, feeding flamingos, ‘islands’ of prehistoric coral, shooting geysers, hotels made entirely of salt, and bizarre eroded rock structures.