U.S. Route 51 is a north–south United States highway that runs for 1,286 miles (2,070 km) from the western suburbs of New Orleans, Louisiana to within 100 feet (30 m) of the Wisconsin-Michigan border. Much of the highway in Illinois and southern Wisconsin runs parallel to or overlaps Interstate 39. The highway's northern terminus is between Hurley, Wisconsin and Ironwood, Michigan, where it ends with a T interchange at U.S. Route 2. Its southern terminus is Laplace, Louisiana, ending at U.S. Highway 61.

In addition to singing about U.S. Highway 61 on his album Highway 61 Revisited, musician Bob Dylan also commemorated Highway 51, covering Curtis Jones' folk song "Highway 51 Blues" on his eponymous album Bob Dylan. The North Mississippi Allstars also paid tribute to the highway in the title track of their album 51 Phantom.