While it’s common to take the U.S. Interstate Highway System for granted, it had a long gestation period before coming to fruition beginning in the mid-20th century.
Until the 1930s, most American roads were made of dirt. Roadbuilding was mostly the jurisdiction of township and county officials, and the federal Office of Public Roads was a small division in the U.S. Dept. of Agriculture, focused primarily on improving farm-to-market roads. One of the earliest proponents of a national highway system was Edward J. Mehren, a civil engineer and the editor of Engineering News-Record.