List of highways numbered 400

The following highways are numbered 400:

Australia

 * Murray Valley Highway

Canada

 * Ontario 400.svg Ontario Highway 400

Croatia

 * Državna cesta D400.svg D400 road

Ireland

 * R400 Regional Route Shield Ireland.png R400 road

Japan

 * Japanese National Route Sign 0400.svg Japan National Route 400

Korea, South

 * Korea Expressway No.400.svg Capital Region Second Ring Expressway

South Africa

 * SA road R400.svg R400 road in the Eastern Cape

Spain

 * ESP N-400.svg N-400 road

Turkey

 * , a west–east state road in Turkey running from Datça, Muğla Province to Esendere at the Iranian border.

United Kingdom

 * UK road A400.svg A400 road in London
 * B400 road (Chancery Lane)

United States

 * US 400.svg U.S. Route 400
 * Arkansas 400.svg Arkansas Highway 400
 * Florida 400.svg Florida State Road 400
 * Georgia 400.svg Georgia State Route 400
 * Elongated circle 400.svg Kentucky Route 400
 * Louisiana 400.svg Louisiana Highway 400
 * MD Route 400.svg Maryland Route 400, a former state highway
 * Nevada 400.svg Nevada State Route 400
 * New York:
 * NY-400.svg New York State Route 400
 * Erie County 400 NY.svg County Route 400 (Erie County, New York)
 * NC 400.svg North Carolina Highway 400
 * Pennsylvania Route 400 (official designation for Pennsylvania Route 380)
 * Ellipse sign 400.svg Puerto Rico Highway 400
 * South Carolina 400.svg South Carolina Highway 400
 * Secondary Tennessee 400.svg Tennessee State Route 400
 * Texas:
 * Texas Spur 400.svg Texas State Highway Spur 400
 * Texas FM 400.svg Farm to Market Road 400
 * Utah:
 * Road 400 (Cottonwood Canyon Road)
 * Virginia 400.svg Virginia State Route 400
 * Virginia State Route 400 (former)