Factual error: When Ray is looking at the map of Arizona to travel to Phoenix to see the restaurant with the "golden arches", it shows Sun City. Sun City wasn't created as a community until the early 60's.
Factual error: In a scene in Illinois, when the camera is panning on churches and civic buildings, a 50-star U.S. flag is shown flying above one building. The U.S. flag had 48 stars at the time.
Factual error: Numerous outdoor scenes in San Bernardino taking place during the 1950's depict a railroad crossing with automatic crossing gates, which were patented in 1966.
Factual error: The scene where Ray Kroc is looking at a map to drive out to San Bernardino, CA to visit the McDonald brothers shows the city of Santa Clarita, CA. There was no such city in the 1950's, as Santa Clarita was not founded until 1987. It also shows Moreno Valley as a major city next to Riverside. Moreno Valley did not exist as a city until 1984. Also, Irvine is shown as a major city, and it existed only as a ranch at the time of Kroc's trip to San Bernardino.
Factual error: While Ray is driving southbound to Phoenix, the highway is marked "U.S. route 17." The actual US 17 is a north-south highway running from Virginia to Florida. There is an interstate 17 which runs to Phoenix, but it did not exist at the time either.