Nevados de Quimsachata Volcanic Complex is a 8 km (5 mi)-long volcanic group on a north-south alignment along the border between Bolivia and Chile, overseeing Chungara Lake. It contains three peaks, all stratovolcanoes. Quimsa means three in the Andean Aymara language, while some local people call these the "Three Sisters". The group is formed N to S by Volcán Humarata - 5,730 m (18,799 ft), Volcán Acotango - 6,052 m (19,856 ft) and Cerro Capurata - 5,990 m (19,652 ft) (also known as Cerro Elena Capurata). The active Volcán Guallatiri, to the west of Cº Capurata is not part of the group. The Acotango stratovolcano is the central and highest of the three. It is in a fairly advanced stage of dissection, but a morphologically youthful lava flow on its northern flank suggests Holocene activity. Humarata, with a summit crater breached to the ESE, and Capurata, a complex of lava domes and associated pyroclastic-flow deposits, may also have been active during the Holocene.