“GRUTAS DE COCONÁ” whose name means “Aguas Hondas”, is an ANP, under the name of Natural Monument, located on the hill of the same name, due to its geological structure of stalagmites and stalactites and for its ecological and cultural importance, to the being home to many species, some of them very rare, strange blind fish live in its underground waters; The area was declared a Natural Monument in 1988, with the purpose of protecting it from the environmental impact generated by human activity. In 1979, during excavation work to install the light and sound system inside the grotto, mammoth and megatherium bones were discovered and unearthed, which are currently in the National Museum of Anthropology and History in Mexico City.