ABOUT U.S. HIGHWAYS/INTERSTATES

Origins of the U.S. Numbered Highway System 
http://www.fhwa.dot.gov/infrastructure/numbers.htm

Old National Highways and Trails
http://www.marion.ohio-state.edu/fac/schul/trails/national/natlist.html

Single and Two StateTrails
http://www.marion.ohio-state.edu/fac/schul/trails/state/statelist.html

U.S. Highways
http://www.route-specific.com/Route_Specific2.htm

Interstate Numbers
http://www.ihoz.com/basic.html

Interstate Beltways & Spurs
http://www.route-specific.com/Route_Specific3.html

U.S. Byways
http://byways.org

U.S. Interstates
http://www.route-specific.com/Route_Specific4.html

U.S. States and Capitals
http://www.route-specific.com/Route_Specific1.html

See Also:
Transportation Systems Management