List of Interstate Highways in Louisiana

The Interstate Highway System in Louisiana consists of 933.84 mi of freeways constructed and maintained by the Louisiana Department of Transportation and Development (La DOTD).

The system was authorized on June 29, 1956 when President Dwight D. Eisenhower signed into law the Federal Aid Highway Act of 1956. The Louisiana Department of Highways, predecessor of the DOTD, began construction shortly afterward on its portion of the system, to which approximately 686 mi was initially allotted. 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. 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.