On a wintery March 3, 1989, an eastbound Burlington Northern freight climbs over Marias Pass just west of Summit, Montana, beneath the towering peaks of Glacier National Park. The train is all-EMD powered by GP40M No. 3501, GP39M No. 2808, SD40-2B No. 7502 and GP39-2 No. 2723. Leader No. 3501 is a former CB&Q GP40 that was remanufactured by Morrison-Knudsen in 1988.