The National Highway System (NHS) is a specially-designated network of the most important roadways in the United States, per criteria established by the Federal Highway Administration (FHWA). The routes have economic, defense, and mobility importance, and include the following:

  • Interstate freeway system
  • Strategic Highway Network System routes (which serve defense-related facilities)
  • Intermodal connectors (primarily roadways that serve major freight and passenger terminals)
  • Federal-aid Principal Arterial routes  (added to NHS per Section 104 of the 2012 transportation reauthorization legislation – MAP-21)
  • Other related, major highways

NHS is a designation on top of other designations. Interstate routes, for example, are part of the NHS and part of the Interstate highway system. Many of the NHS components are state or local routes, and they remain such while also being designated as part of the NHS.

Roads included in the NHS are eligible for National Highway Performance Program (NHPP) funding.   NHS-designated roads may be subject to different requirements, such as those regulating outdoor advertising and junk yards.

Special facilities and terminals in Central Ohio that are directly served by NHS connections include:
CSX Buckeye Yard
CSX Marysville terminal
CSX Marion terminal
Rickenbacker Norfolk-Southern terminal
Columbus downtown Greyhound bus terminal
Port Columbus International Airport
Rickenbacker International Airport
Defense Supply Center Columbus

More info:
MORPC map of NHS routes in 7-county Central Ohio area (identified routes are subject to verification with the Ohio Department of Transportation and FHWA)
Federal Highway Administration NHS link and maps