Montauk Lighthouse, New York

George Washington, as a young engineer, selected the site for the lighthouse at Montauk, at the eastern end of Long Island. He surveyed the land, estimated the erosion rates of the sandy bluffs, and chose a location 60 meters back from the cliff edge that he estimated would be safe from erosion for at least 200 years. His calculations were remarkably accurate. Between 1868 and 1972, the cliff retreated 21 meters, just short of the 30 meters per century that Washington had calculated. A seawall that now protects the lighthouse may prolong its existence beyond George Washington's expectations.