<P> Fred Astaire, whose last movie musical had been Silk Stockings eleven years earlier, and who had concentrated on his TV specials in the interim, was persuaded at the age of sixty - nine to return to the screen to portray the title character . Given his status as a screen legend and to accommodate his talents, the role was given a musical presence it had not had on stage, and he was given top rather than the original third billing . </P> <P> While a construction crew transformed more than nine acres of backlot into Rainbow Valley, complete with a narrow gauge railway, schoolhouse, general store, post office, houses, and barns, Coppola spent five weeks rehearsing the cast, and before principal photography began, a complete performance of the film was presented to an audience on a studio soundstage . In the liner notes she wrote for the 2004 Rhino Records limited, numbered edition CD release of the soundtrack, Clark recalls that old - Hollywood Astaire was befuddled by Coppola's contemporary methods of film - making and balked at dancing in "a real field with cow dung and rabbit holes ." Although he finally acquiesced to filming a sequence in the Napa Valley near Coppola's home, the bulk of the movie was shot on studio soundstages and the backlot, leaving the finished film with jarring contrasts between reality and make - believe . </P> <P> Clark was nervous about her first Hollywood movie and particularly concerned about dancing with old pro Astaire . He later confessed he was just as worried about singing with her . The film was partially choreographed by Astaire's long - time friend and collaborator Hermes Pan, who was fired by Coppola during filming . Finian's Rainbow proved to be Astaire's last major movie musical, although he went on to dance with Gene Kelly during the linking sections of That's Entertainment, Part 2 . </P> <P> Clark recalls that Coppola's approach was at odds with the subject matter . "Francis...wanted to make it more real . The problem with Finian's Rainbow is that it's sort of like a fairy tale...so trying to make sense of it was a very delicate thing ." Coppola opted to fall somewhere in the middle, with mixed results . Updating the story line was limited to changing Woody from a labor organizer to the manager of a sharecroppers' cooperative, making college - student Howard a research botanist, and a few minor changes to the lyrics in the Burton Lane - E.Y. Harburg score, such as changing a reference to Carmen Miranda to Zsa Zsa Gabor . Other than that, the plot remains firmly entrenched in an era that predates the Civil Rights Movement . </P>

Where was the movie finian's rainbow filmed