<P> Gale Sondergaard was originally cast as the Wicked Witch . She became unhappy when the witch's persona shifted from sly and glamorous (thought to emulate the wicked queen in Disney's Snow White and the Seven Dwarfs) into the familiar "ugly hag". She turned down the role and was replaced on October 10, 1938, just three days before filming started, by MGM contract player Margaret Hamilton . Sondergaard said in an interview for a bonus feature on the DVD that she had no regrets about turning down the part, and would go on to play a glamorous villain in Fox's version of Maurice Maeterlinck's The Blue Bird in 1940; Margaret Hamilton played a role remarkably similar to the Wicked Witch in the Judy Garland film Babes in Arms (1939). </P> <P> According to Aljean Harmetz, the "gone - to - seed" coat worn by Morgan as the wizard was selected from a rack of coats purchased from a second - hand shop . According to legend, Morgan later discovered a label in the coat indicating it had once belonged to Baum, that Baum's widow confirmed this, and that the coat was eventually presented to her . But Baum biographer Michael Patrick Hearn says the Baum family denies ever seeing the coat or knowing of the story; Hamilton considered it a concocted studio rumor . </P> <P> Filming commenced October 13, 1938, on the MGM lot in Culver City, California, under the direction of Richard Thorpe (replacing original director Norman Taurog, who filmed only a few early Technicolor tests and was then reassigned). Thorpe initially shot about two weeks of footage (nine days in total) involving Dorothy's first encounter with the Scarecrow, as well as a number of sequences in the Wicked Witch's castle, such as Dorothy's rescue (which, though unreleased, comprises the only footage of Ebsen's Tin Man). </P> <P> According to most sources, ten days into the shoot, Ebsen suffered a reaction to the aluminum powder makeup he wore . He was hospitalized in critical condition, and subsequently was forced to leave the project; in a later interview (included on the 2005 DVD release of The Wizard of Oz), he recalled the studio heads appreciated the seriousness of his illness only after seeing him in the hospital . Filming halted while a replacement for him was found . No full footage of him as the Tin Man has ever been released--only photographs taken during filming and makeup test photos . His replacement, Jack Haley, simply assumed he had been fired . Author and screen - writer George MacDonald Fraser offers an alternative story, told to him by Burt Lancaster's producing partner, Jim Hill, that Ebsen had refused to be painted silver and was fired . </P>

Where was the wizard of oz filmed at