Eastbound Pennsylvanian on Horseshoe Curve, 2016. — Amtrak: History of America's Railroad
Visiting the Horseshoe Curve – Train Aficionado
21 Horseshoe Curve Pennsylvania Stock Photos, High-Res Pictures, and Images - Getty Images
Historic Rail Summer 2021 Catalog by Historic Sales - Issuu
File:Amtrak Pennsylvanian on Horseshoe Curve (8991394046).jpg - Wikipedia
PRR Tracking the Light
History Blog
History Blog
HawkinsRails - Horseshoe Curve
Photo after 3rd and 4th track finished at Horseshoe Curve. Notice the park and the stone horseshoe on the slope.
Connections of Steam. Of all man's creations borne out of…, by Robert John Davis, Raconteur
Pennsylvanian pulling into Greensburg, 2016. — Amtrak: History of America's Railroad