Calbuco is a stratovolcano in southern Chile, located southeast of Llanquihue Lake and northwest of Chapo Lake, in the Los Lagos Region, and close to the cities of Puerto Varas and Puerto Montt. With an elevation of 2,015 meters above sea level, the volcano and the surrounding area are protected within the Llanquihue National Reserve. The most recent eruption, a major VEI 4 event, happened with little warning on April 22–23, 2015, followed by a smaller eruption on April 30.