National Road
The National Road—formerly the Cumberland Road and later celebrated as "Main Street of America"—was the United States' first great federally financed highway and a proving ground for national‑scale internal improvements. Originating at the head of navigation on the Potomac River in Cumberland, Maryland, the 4-rod (66 ft; 20 m) wide engineered turnpike was authorized on March 29, 1806, when President Thomas Jefferson signed "An Act to regulate the laying out and making a road from Cumberland … to the State of Ohio".