It was used to serve vacationers and commuters alike before the Great War. By 2281, Caesar's Legion has used the old highway to transport its legionaries and supplies as well as using it to display crucified members of the Twisted Hairs alongside it in the areas the Legion controls.
The highway serves as the southern border of the Mojave Preserve. The I-40 connects many territories together, crossing the continental United States before the war. In the Mojave Wasteland region, the highway passes through Flagstaff in Arizona, intersects with Highway 93, progresses through Bullhead City, running along the bottom of the Mojave until entering California, where it intersects with Highway 95 and merges with I-15.
I-40 is mentioned only in Fallout: New Vegas.
Behind the scenes
I-40 is based on the real world Interstate 40.
- Legion slave ledger: "Of particular interest is the fate of the Twisted Hair tribe of Arizona, who formed an alliance with Caesar to serve as his army's scouts during the conquest of that region. Once the Arizona wastes were pacified, the Legion turned on its erstwhile allies, stripped them of their tribal identity, and forced them into slavery. Those who resisted were crucified along the remains of I-40."