Overview of the National Highway System

Congress designated the National Highway System when it passed the Intermodal Surface Transportation Efficiency Act of 1991.  The National Highway System consists of approximately 155,000 miles of roads nationally.  The interstate system, the defense strategic highway network (STRAHNET) and all strategic highway connectors are included in the National Highway System.  The states also submitted for Congress' approval many routes that the states felt had significant and national use.

Below is a map that shows the National Highway System in Indiana.   Specific maps for some areas are listed below.  These maps are in the PDF format. If you need Adobe Acrobat to read them, you can  now.

Maps of the National Highway System in other states.