From the web site:
The Carriage Roads and stone bridges in Acadia National Park (a 57 mile network of woodland roads free of motor vehicles) were financed and directed by John D. Rockefeller, Jr., between 1913 and 1940, for hikers, bikers, horseback riders and carriages. Approximately 45 miles of Carriage Roads within the park allow the activities of cross-country skiing and limited snowmobiling. (Carriage Road photos)
The Carriage Roads are the best example of turn of the century “broken stone” roads in America today. Granite from Mount Desert Island was quarried by the construction crews for road material and bridge facing. Native vegetation such as fern and wild blueberries was tastefully used to landscape the roadside. (Click Carriage Roads for a map furnished by U.S. National Parks.)
Mainer