Cerro Toco is a stratovolcano located in the eastern part of the Atacama Desert in Chile's II Region (Antofagasta), approximately 6 km south of the border between Bolivia and Chile and 12 km SE of the Juriques and Licancabur volcanoes. It conforms the north eastern extreme of the Purico Complex, a pyroclastic shield made up by several stratovolcanoes, lava domes and a maar. Cerro Toco is located in the Chajnantor Scientific Reserve, as is most of the Purico Complex. The Atacama Cosmology Telescope and the Huan Tran Telescope are located on the western side of the mountain at approximately 5200 m.