50th Anniversary of Interstate Highways 1956-2006

In the Federal-Aid Highway Act of 1944, Congress acted on recommendations from Interregional Highways . The legislation called for designation of a National System of Interstate Highways, up to 40,000 miles in length, to connect principal metropolitan areas, cities, and industrial centers, to serve the National Defense, and to connect with routes of continental importance in Mexico and Canada at suitable border points. Under the leadership of President Eisenhower, the question of how to fund the Interstate System was resolved with enactment of the Federal-Aid Highway Act of 1956.

Some Fun Facts for the Colorado Interstate System:

  • Interstate first signed and showed up on Colorado maps in 1961.
  • Highest point on Interstate system is at the Eisenhower Tunnel. – 11,155 feet. Also, it’s the highest vehicular tunnel in the world.
  • The last section of interstate highway to open in Colorado was I-76 between Pecos Street and I-25, in September 1993. Completion of this segment marked the completion of the interstate system in Colorado.

Histories of Colorado Interstates including construction highlights and major incidents for Interstates 25, 70, 225, 76, and 270. Historic photos can be ordered from the Colorado Department of Transportation.

Search the CoSPL catalog for titles of interest on interstates

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