Licancabur is a highly symmetrical stratovolcano on the southernmost part of the border between Chile and Bolivia. It is located just southwest of Laguna Verde in Bolivia. The volcano dominates the landscape of the Salar de Atacama area. The lower two thirds of the northeastern slope of the volcano belong to Bolivia, 5,400 m (17,717 ft) from the foot at 4,360 m (14,304 ft), while the rest and biggest part, including the higher third of the northeastern slope, the crater and summit, belong to Chile.
The summit and the crater are located entirely in Chile, slightly over 1 km (3,281 ft) to the south west of the international borders, it is about 400 m (1,312 ft) wide and contains a 70 m (230 ft) by 90 m (295 ft) crater lake, Licancabur Lake, which is ice-covered most of the year. This is one of the highest lakes in the world, and despite air temperatures which can drop to -30 °C, it contains planktonic fauna.
Licancabur's most recent volcanic activity produced extensive lava flows which extend 6 km down the northwest and southwest flanks, with older lava flows reaching 15 km (9 mi) and pyroclastic flow deposits as far as 12 km (7 mi) from the peak. Extensive Inca ruins, located on the summit, provide proof of pre-Columbian ascents as well as evidence for the absence of major eruptions over the past 500-1.000 years.