Two pioneering American roadways

This paper discusses the historical background and significance of Delaware's DuPont Highway (1908–23) and New Jersey's Route 1 extension (1923–32). Thomas Coleman du Pont envisioned a multi-modal roadway that was far ahead of its time, including the use of bypasses, a concept previously only used by railroads. The Route 1 extension, which was designed by an engineering team led by William G. Sloan of the New Jersey State Highway Commission, featured the innovative use of economic theories and actual traffic studies to guide the design of one of America's first limited-access motorways. It was planned using economic theories of location adapted from railroad practices.