National Highway System

States

The National Highway System (NHS) includes the Interstate Highway System as well as other roads important to the nation’s economy, defense, and mobility. The NHS was developed by the Department of Transportation (DOT) in cooperation with the states, local officials, and metropolitan planning organizations (MPOs).

Where is the NHS?

You can view state maps of the National Highway System. These maps reflect updates in accordance to the NHS memorandum dated September 28, 2012 as required by Section 1104 of the Moving Ahead for Progress in the 21st Century Act (MAP-21).

(PDF Map source: NHS Shapefile (Zip 102Mb, Version 20221230) Updated: 1/5/2023 and Shapefile Data Item Definitions (metadata (Zip 38Kb)))