Factual error: The scene at the car lot in the beginning is supposed to take place in Chicago. Mountains and palm trees are visible in one angle when Clark is talking to Ed about the car being the wrong one.
Directed by: Harold Ramis
Starring: Eugene Levy, Chevy Chase, John Candy, Randy Quaid, Anthony Michael Hall, Beverly D'Angelo, Jane Krakowski, Eddie Bracken, Christie Brinkley, Imogene Coca
Factual error: The scene at the car lot in the beginning is supposed to take place in Chicago. Mountains and palm trees are visible in one angle when Clark is talking to Ed about the car being the wrong one.
Revealing mistake: In the film's first scene, as Clark and Russ Griswold make a left hand turn to pull into the used car lot in Chicago, the upper quarter of the screen shows mountains and palm trees in the background, which is an impossibility for Chicago. I believe the nearest mountain range to Chicago is in Arkansas and the nearest palm trees reside in Louisiana. (This scene was filmed in California, which explains the mountains and palm trees, BUT nonetheless a mistake.)
Cousin Vicki: I'm going steady, and I French kiss.
Audrey Griswold: So? Everybody does that.
Cousin Vicki: Yeah, but Daddy says I'm the best at it.
Trivia: The script was based on writer John Hughes short story called "Vacation 58" which was based on a real life trip he took as a child with his parents in 1958.
Question: I've always found it odd that although Wallyworld is closed, the car park is still open and accessible. Is this normal for closed US parks, or could it be considered a goof?
Chosen answer: The parking lot is huge. There's really not any way to close the lot itself, but even if there were gates, Clark would probably have been oblivious to them by then.