Salar de Uyuni is known as the largest salt flat in the world with its almost 11,000 meters. It is located in two of Bolivia's nine departments, Potosi and Oruro. It was formed following the transformations between some prehistoric lakes. The Salar de Uyuni contains 50-70% of the world's lithium reserves, currently being mined. It is also home to a variety of pink flamingos and is home to Salt Hotels, tourist hotels made entirely of salt. After it rains and the water settles on top of the salt, it causes a mirror effect that reflects the sky onto the ground. According to Aymara legend, the Tunupa, Kusina and Kusku mountains, the mountains surrounding the Salar, were once giant peoples. The legend continues that Tunupa married Kusku, but Kusku grabbed Kusina and ran away. Tunupa was devastated and as she nursed her son, her tears and milk mixed thus forming the Salar. Tunupa is still considered a deity by locals today and claims that the Salar de Uyuni should be called "Salar de Tunupa" in his name.