Acotango is the central and highest of a group of stratovolcanoes straddling the border of Bolivia and Chile. It is 6,052 metres (19,856 ft) high. The group is known as Kimsa Chata and consists of three mountains: Acotango, Umurata north of it and Capurata south of it.
The volcanoes Acotango (left) and Capurata (right)
Guallatiri is a volcano in Chile with an elevation of 6,060 to 6,071 m. It is located southwest of the Nevados de Quimsachata volcanic group; some sources classify Guallatiri as a member. Guallatiri is a stratovolcano with numerous fumaroles around the summit. The summit may be a lava dome or volcanic plug, while the lower flanks of the volcano are covered by lava flows and lava domes. The volcano's eruptions have produced mostly dacite along with andesite and rhyolite. Past glaciation has left moraines on Guallatiri.
Fumarole activity in the crater of Guallatiri
Landscape under Guallatiri, with the fumaroles visible