History of Interstate Highway

The interstate system was certified by the Federal-Aid Highway Act of 1956, generally identified as the National Interstate and Defense Highways Act of 1956. It was lobbied for by most important U.S. automobile manufacturers and championed by President Dwight D. Eisenhower, and was influenced by both his experiences as a young soldier crossing the country in 1919 next the route of the Lincoln Highway, and by his gratitude of the German autobahn network.

Planning for a system of new superhighways started in the late 1930s, even previous to federal commitment to build the Interstate highway system came in the 1950s. The Construction on the world's first public limited-access highway, the Bronx River Parkway, had started in New York as early as 1907. By the 1920s, longer highways like the New York City parkway system had been built as part of local or state highway systems. As automotive traffic increased, planners saw require for such an interrelated national system to add-on the existing, mostly non-freeway, U.S. Highway system. The General location of national system of interstate highways, together with all additional routes at urban areas selected in September, 1955 maps what became the interstate system, and is unofficially known as the Yellow Book.

Although the construction on the Interstate Highway system continues, it was authoritatively regarded as complete in 1991 (though 5.6 miles of the unique planned route remain either unconstructed or not yet open). The initial cost guess for the system was $25 billion over twelve years; it ended up costing $114 billion, taking 35 years to complete. As of 2004, the system contains over 42,700 miles (68,500 km) of roads, all at smallest amount four lanes wide.