This UN-listed biosphere reserve of El Cielo is a rich habitat covering 1440 square kilometres. It's mostly covered by steep-sided, forested sierra and river valleys. What is unique about Reserva de la Biosfera El Cielo is the diversity of its climate zones; it basically marks the transition between the tropical, semi-desert and temperate ecosystems. The forest is home to half of Mexico’s bird species and forty kinds of bats, as well as other rare animals such as black bears, six species of wild cat, and grey foxes. Different varieties of flora, including different types of orchids, bloom in the altitude zones of 800m to 1400m.