The majority of the location filming occurred in Northeastern Pennsylvania in 1969. The town of Eckley, was so unchanged from its 1870s appearance that the only major alterations needed for filming were to remove television antennas and install underground electric wiring. A wooden coal breaker which was built as a prop and is featured extensively in the film, partially stands to this day. The movie resulted in the town's being saved from demolition. It was afterward converted into a mining museum under the control of the Pennsylvania Historical and Museum Commission. Portions of the film were also shot in Jim Thorpe. The courtroom, where the trial scene was filmed is in the Carbon County Courthouse, used for trials until 1996. Railroad scenes were filmed on the now-defunct Carrol Park & Western Railroad in Bloomsburg.