U.S. 42 links Cleveland, OH to Louisville, KY.
U.S. 43 runs from Columbia, TN to Mobile, AL.
U.S. 44 goes from Plymouth, MA to Kerhonkson, NY.
U.S. 45 connects Ontonagon, MI to Mobile, AL. It goes through an actual town called Metropolis, IL (population 6000). Because it has the same name as a town depicted in comic books, Metropolis is referred to as "Superman's Hometown." US 45 splits into US 45E and US 45W between South Fulton and Jackson, TN.
U.S. 46 runs from Fort Lee to Warren County, NJ; it originally extended as far as Stroudsburg, PA.
U.S. 47 has never been used in any known proposal.
U.S. 48 runs from Strasburg, VA to Weston, WV. The designation has also been used for two other routes: Originally, it was applied to a routing in the San Francisco Bay Area; later it was signed on an expressway-grade road between Hancock, MD and Morgantown, WV (now Interstate 68).
U.S. 49 links Piggott, AR to Gulfport, MS. It splits into US 49E and US 49W at Tutwiler, MS. The two routes rejoin at Yazoo City, MS. In the song "Highway 61," blues singer Robert Johnson sold his soul to the devil at the title road's junction with Highway 49.
U.S. 50 goes from Ocean City, MD to West Sacramento, CA. It once connected to San Francisco via Stockton, CA. The Nevada section is known as the loneliest stretch of highway in America. The highway also runs through Jefferson City, MO and Carson City, NV, two state capitals that are not served by any Interstate highway.
