By definition an
interstate highway should go between two or more states. However, there are several highways in the United States which were built as part of the
Eisenhower system which are actually intrastates meaning that they only go between cities in one state and never cross borders. Examples include:
- H1, H2, and H3 which all service the island of Oahu, Hawaii
- I-45 which goes between Dallas and Galveston in Texas
- I-27 which goes between Amarillo and Lubbock in Texas
- I-49 which goes between Shreveport and Lafayette in Louisiana
- I-12 which goes between Baton Rouge and Slidell in Louisiana
- I-17 which goes between Flagstaff and Phoenix in Arizona
- I-19 which goes between Tucson and Nogales in Arizona
- I-4 which goes between Daytona and Tampa in Florida
- I-16 which goes between Macon and Savannah in Georgia
- I-96 which goes between Norton Shores and Detroit in Michigan
Please note that I am not including three digit "beltways" such as I495 Long Island Expressway in New York.