Cumberland Road
Vandalia was the western terminus of the Cumberland or National Road which extended eighty feet wide for 591 miles from Cumberland, Maryland through Pennsylvania, Ohio, and Indiana. Illinois construction by the Federal Government began in 1811 and ceased in 1838, the approximate cost being seven million dollars.
Marker is at the intersection of 4th Street and Gallatin Street, on the right when traveling north on 4th Street.
Courtesy hmdb.org