Photo from Roadside highway turnout Roadside turnout with picnic area and a historical marker - North side of highway. 'Historic New York - The Adirondacks - The Adirondack Mountains, consisting of rocky peaks, sheer cliffs and narrow valleys, also have wooded slopes and sparkling lakes. Forty-three mountains have elevations 1000 ft. or higher. Mount Marcy, with an altitude of 5344 feet, is the highest. Near Marcy's summit is Lake Tear-of-the-Clouds, the source of the Hudson River.'