The system was authorized on June 29, 1956 when PresidentDwight D. Eisenhower signed into law the Federal Aid Highway Act of 1956.[1] The Louisiana Department of Highways, predecessor of the DOTD, began construction shortly afterward on its portion of the system, to which approximately 686 miles (1,104 km) was initially allotted.[3] The first road segment in the new system was officially opened and dedicated on February 24, 1960 and consisted of a portion of the Pontchartrain Expressway (I-10) in New Orleans.[4] Two months later, the first Interstate Highway shields installed in Louisiana accompanied the opening of a portion of I-20 near Ruston on April 23.[5]
Louisiana's primary north–south route, connecting I-10 and I-20 via Alexandria; final gap in Shreveport is under construction and southern extension from Lafayette to New Orleans is planned
^Special Committee on U.S. Route Numbering (July 6, 1977). "Route Numbering Committee Agenda"(PDF) (Report). Washington, DC: American Association of State Highway and Transportation Officials. p. 2. Retrieved May 26, 2017 – via Wikimedia Commons.
^Wagner, Robert (January 26, 1958). "Interstate Highway System Construction Work Is Begun". The Times-Picayune. New Orleans. sec. 8, p. 12.