Construction of the National Road 1811 – 1830’s
Road construction begins at Cumberland, Maryland. The base of the road is constructed of stone, with a gravel/sand surface. The road’s surface measures 32 feet in width of which the center 20 feet is comprised of broken stones placed to a depth of 18 inches at the middle and 12 inches at the sides. The base’s lower layer consists of broken stones passed through a seven inch ring. The upper layer is also broken stone passed through a three inch ring. The surface composition is gravel or sand compacted with a three ton roller.