The early federally funded highway from Cumberland, Maryland, toward Illinois was the National Road.
Also called the Cumberland Road, it was authorized by Congress in 1806, with construction beginning in 1811. The original route ran west from Cumberland across the Allegheny Mountains to Wheeling, Virginia, now in West Virginia, on the Ohio River. Later extensions carried it through Ohio and Indiana to Vandalia, Illinois.
Federal construction reached Vandalia by 1839, covering roughly 591 miles from Cumberland. The road was a major experiment in federally funded internal improvements and helped settlers, merchants, and stagecoaches move into the developing interior. It also triggered constitutional debates about how much power the federal government had to build transportation infrastructure.
The National Road is often confused with the Wilderness Road, an older route associated with Daniel Boone and migration through the Cumberland Gap. It is also not the Lincoln Highway, a 20th-century automobile route. Much of the historic alignment later became U.S. Route 40, and surviving bridges, mile markers, and tollhouses remain important historic features.