Exterior shots of the train set in the rural western U.S. were filmed on the Canadian Pacific line from the Crowsnest Pass to Lethbridge, Alberta. Interiors were shot in a studio, with the sets mounted on rubber tires so they could be rocked. To simulate the train passing through the shadow of a tree, a series of crew members would successively move obstructions in front of each of a row of lights shining into the windows.
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