Acadia National Park Carriage Road System

From 1915 to 1940, John D. Rockefeller Jr. financed, designed, and directed the construction of roughly 57 miles of crushed stone carriage roads across Mount Desert Island — about 45 miles of which remain maintained within park boundaries today. Sixteen of the system's 17 stone-faced, steel-reinforced concrete bridges were financed by Rockefeller. Motor vehicles are prohibited. Hikers, cyclists, horseback riders, and cross-country skiers use the roads year-round, with closures each spring to protect the gravel surface from thaw damage.