Much of this episode was filmed at Harpers Ferry, W.Va., and Harpers Ferry National Historical Park. Many of the scenes were shot in actual historic buildings dating back to 1850. The distant images of Johnstown is actually the town of Harpers Ferry, digitally altered to look like a city located in a valley. Harpers Ferry is actually located at the confluence of the Potomac and Shenadoah rivers in the Shenandoah Valley.
One scene was actually filmed at Lyndhurst, Jay Gould's mansion. Gould, a railroad baron and profiteer, is featured in the series. Lyndhurst is open for tours.