A 1997 photo of the mileage sign at the start of I-40 in Barstow, showing the distance to the freeway's eastern terminus in Wilmington, North Carolina. This sign had been stolen several times.[2]
I-40 goes through the Mojave Desert on the entirety of its run through California. The highway starts its eastward journey at a junction with I-15 in Barstow. The freeway passes through Marine Corps Logistics Base Barstow before leaving the city limits. I-40 provides access to the town of Daggett but passes south of the town. After passing south of the Barstow-Daggett Airport, I-40 goes through Newberry Springs and Ludlow before traveling along the south end of Mojave National Preserve. Several miles east of the preserve, I-40 intersects U.S. Route 95 (US 95), and the two highways run concurrently into the city of Needles. In Needles, US 95 continues south while I-40 continues east through Mojave National Preserve and across the Colorado River into Arizona.[3] The maximum speed limit for the entire California segment of I-40 is 70 mph (110 km/h).
In 1957, the California Department of Highways proposed that the route be numbered as I-30 because of the already existing US 40 in the state. However, this was rejected, and, eventually, US 40 was decommissioned in favor of I-80.
Today, the Needles Freeway replaced the former US 66 across the Mojave Desert. As a result, a number of communities along the former route, like Amboy, have become ghost-towns.[10]
In the early 1960s, Project Carryall, a component of Project Plowshare, would have detonated 22 nuclear explosions to excavate a massive roadcut through the Bristol Mountains to accommodate a better alignment of I-40 and a new rail line. This proposal was abandoned by the California State Department of Highways in 1968.[11][12] The section between Ludlow and Needles was constructed using conventional explosives and excavation and designed with culverts for migrating Bighorn sheep and water tanks. It opened to traffic on April 13, 1973.[13]
A sign at that start of I-40 in Barstow showing the distance to Wilmington, North Carolina, had been stolen multiple times.[2]
California does not have any auxiliary Interstate Highways associated with I-40.
One business loop of I-40 exists in the state, running through Needles. It is also designated as Historic Route 66 since it follows the former routing of US 66.
^San Bernardino County Street Atlas (Map). Thomas Brothers. 2008.
^"Article 2 of Chapter 2 of Division 1". California Streets and Highways Code. Sacramento: California Office of Legislative Counsel. Retrieved February 6, 2019.
^Federal Highway Administration (March 25, 2015). National Highway System: California (South)(PDF) (Map). Scale not given. Washington, DC: Federal Highway Administration. Retrieved October 15, 2017.
^Natzke, Stefan; Neathery, Mike & Adderly, Kevin (June 20, 2012). "What is the National Highway System?". National Highway System. Washington, DC: Federal Highway Administration. Retrieved July 1, 2012.
I-15 in Barstow
US 95 in Needles
I-40 at the Arizona state line near Topock, AZ.svg)
