Donaldson Mountain is a 4,140-foot summit in the Seward Range of the Adirondack Mountains in northern New York and ranks thirty-third among the Adirondack High Peaks. In Harrietstown, it lies between Seward Mountain and Mount Emmons. Its first documented ascent came on October 14, 1870, when surveyor Verplanck Colvin and guide Alvah Dunning climbed it en route to Seward Mountain. The mountain received its present name in 1924 after a campaign by the Adirondack Mountain Club and Russell M. L. Carson, honoring Alfred Lee Donaldson, author of A History of the Adirondacks. Reached by unmarked trails, it remains a notably remote objective in one of the Adirondacks’ classic rugged mountain groups.