Llullaillaco

Llullaillaco is a dormant stratovolcano on the border of Argentina (Salta Province) - Chile (Antofagasta Region). It is located in the Puna de Atacama, a region of high volcanic peaks on a high plateau near the Atacama Desert, one of the world's driest places. Llullaillaco evolved through two stages. The volcano's base was formed by a broad cone of thick lava flows. About 150,000 years ago, a section of this volcano collapsed, causing a massive debris avalanche that sent deposits eastward into Argentina. The modern-day summit of Llullaillaco was formed on top of the old volcano about 10,000 years ago.

Llullaillaco is the world's second-highest active volcano, after its neighbor, Nevado Ojos del Salado. Coulees are visually impressive structures formed by thick, viscous lava flows from Llullaillaco, which appear in parallel ridges like accordion pleats. The volcano's last known eruption occurred in 1877.

Location: Chile and Argentina border
Height: 6,739 m (22,110 ft)
Parent Range: Andes, Puna de Atacama