Ojos del Salado The elevation of Ojos del Salado has been the subject of debate. The mountain is hidden behind other peaks and thus its height was not appreciated in early research until 1937, when the mountain was climbed by Polish climbers. A 2006 article in Andes Magazine offered that Ojos del Salado may be higher than Aconcagua, although the argument was premised on older, less accurate altitude surveys. The results of these older surveys assigned Ojos del Salado an elevation of , which would have made it nearly higher than Aconcagua. As early as 1955, an estimate was made that the elevation
Ojos del Salado reports indicate the absence of glaciers on Ojos del Salado. Permafrost exists on the mountain and its melting nourishes several lakes; one lake fed by a creek lies at altitude. Ojos del Salado is an active volcano, but the question of whether it should be considered "currently" (or "historically") active is arguable. According to the Smithsonian Institution's Global Volcanism Program, the most recent known eruption was about 1,300 years ago, with a large margin of uncertainty. However, there is also some evidence for a minor ash emission in 1993, which would definitely qualify the volcano as historically active. The presence