List of highways numbered 51

Australia

• Kamilaroi Highway
• Plenty Road

  Cambodia

• Road 51 (Cambodia)">Road 51 (Iran)">Road 51 (Cambodia)

  Canada

• Alberta Highway 51
• Saskatchewan Highway 51

  Cuba

• Caimito–Salado Road

  Finland

• Finnish national road 51

  France

• A51 autoroute

  Greece

• EO51 road

  Hungary

• M51 expressway (Hungary)

  India

• National Highway 51 (India)

  Iran

• Zobahan Freeway
• Road 51

  Italy

• Autostrada A51

  Japan

• Japan [National Route 51]

  South Korea

• Lebanon

• 51M Coastal Highway

  New Zealand

• New Zealand State Highway 51

  Philippines

• N51 highway (Philippines)

  South Africa

• R51

  Turkey

• , a motorway in Turkey running from Adana to Mersin.

  United Kingdom

• British A51 (Kingsbury-Chester)

  United States

• U.S. Route 51
• Alabama State Route 51
• Arizona State Route 51
• Arkansas Highway 51
• California State Route 51
• Colorado State Highway 51 (1923-1968)
• Florida State Road 51
• * County Road 51 (Hamilton County, Florida)
• Georgia State Route 51
• * Georgia State Route 51 (1920)
• Hawaii Route 51
• Idaho State Highway 51
• Illinois Route 51
• Indiana State Road 51
• Iowa Highway 51
• K-51 (Kansas highway)
• Maryland Route 51
• *Maryland Route 51A
• *Maryland Route 51B
• *Maryland Route 51C
• *Maryland Route 51D
• *Maryland Route 51E
• *Maryland Route 51F
• M-51 (Michigan highway)
• Minnesota State Highway 51
• * County Road 51 (Anoka County, Minnesota)
• * County Road 51 (Ramsey County, Minnesota)
• Missouri Route 51
• Nebraska Highway 51
• * Nebraska Link 51A
• * Nebraska Link 51B
• * Nebraska Link 51C
• * Nebraska Recreation Road 51E
• * Nebraska Recreation Road 51F
• * Nebraska Recreation Road 51G
• * Nebraska Recreation Road 51H
• Nevada State Route 51
• New Hampshire Route 51
• New Jersey Route 51
• * County Route 51 (Bergen County, New Jersey)
• ** County Route S51 (Bergen County, New Jersey)
• * County Route 51 (Monmouth County, New Jersey)
• New Mexico State Road 51
• New York State Route 51
• * County Route 51 (Cayuga County, New York)
• * County Route 51 (Dutchess County, New York)
• * County Route 51 (Erie County, New York)
• * County Route 51 (Essex County, New York)
• * County Route 51 (Franklin County, New York)
• * County Route 51 (Greene County, New York)
• * County Route 51 (Herkimer County, New York)
• * County Route 51 (Madison County, New York)
• * County Route 51 (Oneida County, New York)
• * County Route 51 (Orange County, New York)
• * County Route 51 (Putnam County, New York)
• * County Route 51 (Rensselaer County, New York)
• * County Route 51 (Rockland County, New York)
• * County Route 51 (Saratoga County, New York)
• * County Route 51 (Schoharie County, New York)
• * County Route 51 (Suffolk County, New York)
• * County Route 51 (Sullivan County, New York)
• * County Route 51 (Ulster County, New York)
• North Carolina Highway 51
• Ohio State Route 51
• Oklahoma State Highway 51
• * Oklahoma State Highway 51A
• * Oklahoma State Highway 51B
• Oregon Route 51
• Pennsylvania Route 51
• Rhode Island Route 51
• South Carolina Highway 51
• Tennessee State Route 51
• Texas State Highway 51
• * Texas State Highway Spur 51
• * Farm to Market Road 51
• * Texas Park Road 51
• Utah State Route 51
• Virginia State Route 51
• * Virginia State Route 51 (1928-1950)
• West Virginia Route 51
• * West [Virginia Route 51 (1920s)]
• * West Virginia Route 51 (1930s)
• Wisconsin Highway 51
• Wyoming Highway 51

  Vietnam

• National Road 51 (Vietnam)