<P> During the Chicago Blizzard of 1979, writer John Hughes began developing a short story entitled "Vacation' 58" for an issue of the National Lampoon . While the story ended up being bumped from the initial vacation - themed issue, it was eventually published in September 1979 and subsequently optioned by Warner Bros. "When I brought it to Hollywood, the first guy I brought it to was Jeff Katzenberg who was at Paramount," recalled producer Matty Simmons, who worked as a publisher at the National Lampoon . "He said it would never make a movie, it was too episodic, too consequential . I said,' Yeah, it's a road trip . It's supposed to be episodic . You go from town to town, place to place .' But he didn't like it, so then my agent brought it to Warner Brothers, and I met with them . Most of them said the same thing, but there was one executive over there--a guy named Mark Canton--who really pulled for it and it got made ." Upon Simmons' agreement with Warner Bros., Hughes was assigned the task of adapting his original story into a screenplay . </P> <P> In Hughes' original short story, the theme park was Disneyland . To avoid legal troubles, all of the names associated with Disneyland were altered to sound - alikes . For instance, the park became Walley World, itself a good - natured parody of the Anaheim location, and the mascot, Marty Moose, is reminiscent of Walt Disney's own Mickey Mouse . Similarly, Roy Walley's appearance bears similarities to that of Disney and his name is similar to that of his brother Roy Disney. . </P> <P> In the film, the Walley World theme park is represented by Santa Anita Park in Arcadia, California and Six Flags Magic Mountain in Valencia, California . Santa Anita Park's large parking lot and blue - tinged fascia served as the exterior of Walley World, while all park interior scenes were shot at Magic Mountain . The two roller coasters seen in the film are The New Revolution, which can be recognized by the vertical loop, and Colossus, the double - track wooden roller coaster . </P> <P> The movie's popularity gave rise to an ongoing cultural running gag of using the name "Wally World" (spelled as "Wally" without an "e") as a nickname for real - life retailer Walmart . </P>

What theme park is national lampoon's vacation filmed at