This painting depicts a view from high on Aconcagua, in the Andes Range of Argentina. Alex completed the painting after a climbing expedition on Aconcagua, at 22,841 feet the tallest peak in the Western hemisphere. The Stone Sentinel is one of Alex's many paintings that capture the unique qualities of light found at extreme altitudes. The snow and ice formations depicted in the foreground are known as "penitentes." All proceeds from prints of this painting were donated to the Muscular Dystrophy Association during Alex's year-long fundraising drive. The total number of Limited Edition prints was based on the number of contributions received for the Association.