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.)
National Lampoon's Vacation (1983)
Plot summary
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
Clark Griswald has planned a vacation with his family to wally world, but unfortunatly his trip does not go to plan and the trip has a few hilarious problems on the way.
More mistakes in National Lampoon's Vacation
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.
Answer: Harold Ramis voiced Marty Moose.