It is in the Andes of western Argentina near the Chilean border. Mount Aconcagua is located in Argentina. Mount Aconcagua lies in the southern Andes Mountains. It's peaks are located in the province of Mendoza, Argentina while the western flanks lie close to the city of Santiago in Chile. Aconcagua is widely accepted as the highest peak in the Western Hemisphere with the southern summit elevating to 22,736 feet (6,930 meters).