Aconcagua
Aconcagua (), with a summit elevation of , is the highest mountain in both the Southern and Western Hemispheres. It is located in the Andes mountain range, in the Mendoza Province, Argentina, and lies northwest of its capital, the city of Mendoza, about from San Juan Province and from the international border with Chile. The mountain itself lies entirely within Argentina, immediately east of Argentina's border with Chile. Its nearest higher neighbor is Tirich Mir in the Hindu Kush, away. It is one of the Seven Summits.
Monte Pissis
A 1994 Argentine expedition claimed —using GPS technology available at the time— that the elevation of Monte Pissis was , higher than Ojos del Salado. Ten years later, with the use of higher precision systems, several other surveys proved that those measurements were inaccurate: in 2005, an Austrian team performed a DGPS survey of Pissis' summit and found the elevation to be . In 2006 an international expedition surveyed the height on the summit, and found results in agreement with an elevation around . This was later confirmed by a 2007 Chilean-Argentine-European expedition, which surveyed both Ojos del Salado and Monte Pissis and provisionally found the former to be and the latter .