Writer-director John Hughes is famous for setting his films in Chicago, but Ferris Bueller's Day Off is the most Chicagoan of them all. It's the cinematic equivalent of Michael Jordan dressed as a Polish sausage stuffing a ballot box on stage at Buddy Guy's Legends. "Chicago is what I am," Hughes once explained. "A lot of Ferris is sort of my love letter to the city. And the more people who get upset with the fact that I film there, the more I'll make sure that's exactly where I film" (source). You tell 'em, John.
Location, Location, Location
While most of the interiors—save Morris Frye's extravagant garage—were filmed in California, the rest of the film was shot on location in Chicago (source). According to The A.V. Club, Hughes wanted to show off "not just the architecture, but the spirit" of the Windy City. From the observation deck at Sears Tower to the stands at Wrigley Field, shooting on location adds authenticity to the film.
Nobody Graduates in October
Although Ferris Bueller's Day Off takes place in the spring, just before graduation, almost the entire movie was filmed in the fall. The lone exception? The Wrigley Field scenes, which were shot at the Cubs' June 5, 1985 contest against the Atlanta Braves. The Cubs lost 4-2 in extra innings (source). A Cubs loss? Now that's Chicago.
Filming a movie out of season presented just one challenge for the filmmakers: the changing autumn leaves. The scenes in and around Morris Frye's garage required crewmembers to paint the problematic (but beautiful) fall foliage green in order to suggest spring (source). We don't mean digitally, either. This film was shot in 1985 on good ol' fashioned 35 mm Metrocolor film, so painting leaves involved actual paint. And brushes. Maybe even some totally tubular coveralls.