These sierras form part of a semi-arid region of spectacular geological characteristics and reddish coloured landscape. On the western non-mountainous edge of this park lie a series of lagoons which flow into the Desaguadero. The Potrero de la Aguada is a central depression enclosed by walls which have been eroded into fantastic shapes. This park has a large variety of animals, some in danger of extinction: guanacos, foxes, rheas, pumas and condors. The vegetation is mainly spiny shrubs and cacti.