The Salar de Uyuni is known as the largest salt desert in the world at almost 11,000 meters above sea level. It is located in two of Bolivia's nine departments, Potosi and Oruro. It was formed following transformations between a few prehistoric lakes. The Salar de Uyuni contains 50 to 70% of the world's lithium reserves, currently being extracted. It is also home to a variety of flamingos and is home to Salt Hotels, tourist hotels made entirely of salt. After it rains and the water settles on the salt, it causes a mirror effect reflecting the sky on the ground. According to Aymara legend, Tunupa, Kusina and Kusku, the mountains surrounding the Salar, were once home to giant peoples. The legend goes on to say that Tunupa married Kusku, but Kusku grabbed Kusina and ran away. Tunupa was devastated and while she was nursing her son, her tears and milk were mixed, forming the Salar. Tunupa is to this day considered a deity by the locals of the region and argue that the Salar de Uyuni should be named "Salar de Tunupa" in it.