Welcome to the Interstate-Guide!
Welcome to the Interstate-Guide, brought to you by AARoads! Included on this site are guides for every Interstate highway within the Eisenhower Interstate System. Individual pages include basic information and facts, mileage statistics, history and maps, planned improvements and photographs covering Interstate end points.
The Interstate Highway system in 1974.
The Federal Aid Highway Act of 1968 increased the Interstate system by 1,500 miles. The 42,500 mile system then was envisioned for completion in 1980.
Interstate Highway Guides
Designated in 1956, the Eisenhower Interstate System includes over 46,000 miles with routes in each of the 50 states and the U.S. Territory of Puerto Rico. The Federal-Aid Highway Act of 1956 specified a limit of 41,000 miles to be built with Interstate Construction funds. Legislation eventually increased that limit to 43,000. Other legislation allows the Federal Highway Administration to approve additional mileage for freeways adhering to Interstate standards that would be a logical addition or connection. These routes are considered not chargeable, meaning they are not eligible for Interstate Construction funds under the 1956 Act. There are four types of Interstate highways covered on this site:
Interstate business connections (loops and spurs) were approved by AASHTO in 1964 as a method to provide access from the Interstate superhighway to the cities and towns bypassed by the freeway. Included is a complete list of:
- Active Business Loops/Spurs
- Decommissioned Business Loops/Spurs
- Potential Business Loops/Spurs
The Interstate Shield Gallery is now a part of the new Shield Gallery on AARoads. Featured there are not only photos of Interstate highway shields for each state, but also U.S., State, County, Turnpike, and other route shields from throughout the country.
Cataloging most known turnpikes and toll roads, including those that are not part of the Interstate highway system. More recent trends since the mid 2000s see the addition of high occupancy toll, or HOT lanes to many stretches of Interstate highway within various metropolitan areas. These lanes are often free to use for high-occupancy vehicle (HOV)/carpool eligible motorists and open to other traffic at a variable toll rate based upon congestion pricing (higher rates for busy periods, lower rates for off-peak hours). Some Interstates, such as I-595 in Broward County, Florida, include Express Toll Lanes with no HOV provision.
Featuring trivia, factoids, and other information about Interstate Highways
In addition to our list of Interstates, we recommend you also peruse the Official Federal Highway Administration Interstate Route Log and Finder List and Three-Digit Interstates (3dis) at Kurumi.com for additional information on the United States Interstate Highway System.
We are interested in obtaining photos of Interstate Highway endpoints to complete this project. If you have one you would like to share, please see our contact page for email. Credit will be given for all photos on these pages. Contributors to the Interstate-Guide can be found at the Acknowledgments Page. In addition, if you notice a factual error or an omission or have an update, please feel free to email us with relevant information.
Southbound Interstate 5, originally signed with U.S. 101 before it was retracted in 1964, passes through downtown San Diego's S-curve. This view is taken from the Fifth Avenue over crossing, with the Sixth Avenue over crossing visible in the foreground. Photo taken 07/13/06.