In Pixar's Cars, the setting and journey through Radiator Springs were inspired by U.S. Route 66.
Route 66 once connected Chicago and Santa Monica and became famous for roadside businesses, motels, and small communities. Its decline after the Interstate Highway System bypassed many towns provided the historical backdrop for Radiator Springs, a fictional community struggling after traffic moved elsewhere.
Pixar artists and filmmakers researched Route 66 during development, visiting roadside locations and meeting people connected with the highway. Those observations influenced the town's architecture, landscapes, signs, and characters.
Route 66 is not the exact name of the fictional road that Lightning travels in every scene. It is the real cultural and geographic inspiration behind the film's nostalgic portrait of disappearing roadside America.