Nevado Ojos del Salado is a massive stratovolcano in the Andes on the Argentina–Chile border and the highest active volcano in the world at 6,893 m (22,615 ft). It is also the second highest mountain in the Western Hemisphere and Southern Hemisphere and the highest in Chile. It is located about 600 km (370 mi) north of Aconcagua, the highest mountain in the Western Hemisphere at 6,962 m (22,841 ft).

Due to its location near the Atacama Desert, the mountain has very dry conditions with snow usually only remaining on the peak during winter, though heavy storms can cover the surrounding area with a few feet of snow even in summer. Despite the generally dry conditions, there is a permanent crater lake about 100 m (330 ft) in diameter at an elevation of 6,390 m (20,960 ft) on the eastern side of the mountain. This is most likely the highest lake of any kind in the world.

The ascent of Ojos del Salado is mostly a hike except for the final section to the summit which is a difficult scramble that may require ropes. The first ascent was made in 1937 by Jan Alfred Szczepański and Justyn Wojsznis, members of a Polish expedition in the Andes.

Its name comes from the enormous deposits of salt that, in the form of lagoons or “eyes”, appear in its glaciers.