where was the movie shawshank redemption filmed at
Ohio State Reformatory, Malabar Farm State Park, island of Saint Croix and Sandy Point National Wildlife Refuge,
The Shawshank Redemption
 Marvin eventually chose the Ohio State Reformatory in Mansfield, Ohio, to serve as the fictional Shawshank State Penitentiary in Maine, citing its Gothic-style stone and brick buildings. The facility had been shuttered three years earlier in 1990, due to inhumane living conditions.

The 15-acre reformatory, housing its own power plant and farm, was partially torn down shortly after filming was completed, leaving the main administration building and two cellblocks. Several of the interior shots of the specialized prison facilities, such as the admittance rooms and the warden's office, were shot in the reformatory. The interior of the boarding room used by Brooks and Red was in the administration building; exterior shots of the boarding house were taken elsewhere. Internal scenes in the prison cellblocks were filmed on a sound stage built inside a nearby shuttered Westinghouse Electric factory. Since Darabont wanted the inmates' cells to face each other, almost all the cellblock scenes 
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The Shawshank Redemption [SEP] Filming
On a $25 million budget, principal photography took place over three months between June and August 1993. Filming regularly required up to 18-hour workdays, six days a week. Freeman described filming as tense, saying, "Most of the time, the tension was between the cast and director. I remember having a bad moment with the director, had a few of those." Freeman referred to Darabont's requiring multiple takes of scenes, which he considered had no discernible differences. For example, the scene where Andy first approaches Red to procure a rock hammer took nine hours to film, and featured Freeman throwing and catching a baseball with another inmate throughout it.