The dramatic summit spire of Volcán Puntiagudo forms one of the most spectacular volcanic peaks of the Andes. The summit pinnacle, formed as a result of extensive glacial erosion, exposes the volcano's resistant central conduit. Puntiagudo-Cordón Cenizos volcanic chain lies between Lago Rupanco and Lago Todos Los Santos in the Chilean lake district. An 18-km-long fissure system with late-Pleistocene to Holocene scoria cones and small stratovolcanoes extends to the NE and was last active in 1850. Photo by Oscar González-Ferrán (University of Chile).