The
National Road (also known as the
Cumberland Road) was the first major improved highway in the
United States to be built by the
Federal Government. About long, the National Road connected the
Potomac and
Ohio Rivers and was a gateway to the
West for thousands of settlers. When rebuilt in the 1830s, the Cumberland Road became the first U.S. road surfaced with the
macadam process pioneered by Scotsman
John Loudon McAdam.