Stand back, now; this baby's rolling. The Pennsy era signal bridge at Mapleton, PA, situated in a high speed, super-elevated curve, was always an attraction. Westbounds pour on the power coming out of Jacks Narrows and eastbounds stealthily approach as they shoot down the river valley. The image has a certain appeal to me as PRR was my first employer, and I was to retire from UP after 40+ years railroading in a few months. Highball.