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Road sign that says 'West Interstate 40” with a desert landscape in the background.
Interstate 40 sign.

Before the Interstate Highway System, a patchwork of country roads and trails connected the four corners of the United States. One of these routes was Beale’s Wagon Road, built in 1857 by a team led by Lt. Edward Fitzgerald Beale. The team used camels as pack animals while constructing the road.

For nearly 1,000 miles, today’s Interstate 40 (I-40) follows the general route of Beale’s Wagon Road running from Arkansas to California and ending in Barstow. I-40 is part of America’s Interstate Highway System, officially created by President Eisenhower’s Federal-Aid Highway Act of 1956.

In 1957, the California Department of Highways proposed renumbering the route as Interstate 30 because of the already existing U.S. Route 40 in California. However, U.S. Route 40 was decommissioned in California in 1964, as part of a major revamping of the state’s highway numbering system, which eliminated the problem.

Now known in California as the Needles freeway, I-40 heads east from Barstow across the Mojave Desert in San Bernardino County to Needles before crossing into Arizona. The highway is four lanes wide for its entire length within the state. From 1963 to 1966, the U.S. government considered a plan, part of Project Plowshare, to use atomic bombs to excavate a path for I-40 through California.

The project was ultimately abandoned, largely due to the cost of developing the explosives and the unavailability of a “clean” bomb. The last portion of I-40, connecting Wilmington to Raleigh, North Carolina, was completed in the late 1980s. Today, I-40 is 2,559 miles long.

The Interstate Highway System was officially completed in 1991. According to the 1991 Interstate Cost Estimate reported to Congress, construction of the Interstate System cost $128.9 billion and took more than 35 years to complete.

In the 2006 Pixar film “Cars,” Lightning McQueen and Mack are seen driving west on I-40. Currently, the Interstate System spans 46,876 miles long.

The information in this historical feature was originally part of a video series produced by the Assessor-Recorder-County Clerk’s office. 


Additional County Update News – January 29