Which real-world highway inspired the setting of Radiator Springs?

U.S. Route 66 inspired the setting of Radiator Springs.

In Cars, Radiator Springs is portrayed as a once-busy roadside town along historic Route 66. Its businesses decline after an interstate highway bypasses the town, echoing the real economic impact that newer, faster roads had on many Route 66 communities.

Pixar researched the highway closely. Director John Lasseter contacted Route 66 historian Michael Wallis, who led Pixar artists on research trips across the route. The film’s working title was even Route 66 before it was changed to Cars.

A common mix-up is Interstate 40, which appears in the story as the bypass that diverts traffic. I-40 helps explain Radiator Springs’ decline, but it is not the highway that inspired the town’s identity. Route 66 is the canonical answer.