The Guadalupe dam watershed, located at the northeast of Mexico City, is a region of great biodiversity. It's a source of oxygen, drinking water, wood, food, medicinal plants and cultural elements for the inhabitants of the Valleys of Mexico and Toluca. While an important home for the Otomí ethnic group, the watershed also shelters a peculiar species: the mountain axolotl (Ambystoma altamirani), a micro-endemic, endangered amphibian, unique in the world.