Pennsylvania - Railroads
Several railroad viaducts/bridges have their own pages, linked at bottom.
An old inclined plane used by the Allegheny Portage Railroad to scale the namesake mountain range. The up-and-down railroad was a critical east-west link during the age of canals. This plane is in the median of old US Route 22 near Summit, PA.
Horseshoe Curve was a significant engineering accomplishment, allowing trains to scale the Allegheny Mountains west of Altoona at a reasonable grade with reasonable curvature. Of course, switchbacks can't work for trains like they do for automobiles, and the maximum reasonable grade for a train is at best one fourth of what an automobile can handle. The Curve connects three hillsides and spans two valleys, which were build up to support the Curve. Roads running through those small valleys tunnel(ed, in one case) through the railroad embankment.
A panorama from the valley floor below the curve, starting and ending in the northeast and proceeding counterclockwise up the curve's incline.
Now at the same level of the curve, panning in the same direction. Horseshoe Curve is not only still active track, but it carries approximately three trains an hour!
Two of the three Gallitzin Tunnels. Most of the tracks in Gallitzin (which used to connect redundantly) are in disuse or have been torn up, so the left tunnel here was never improved, and a tunnel further south of these two carries no traffic anymore, either.
Tunkhannock Viaduct (Lackawanna RR)
Kinzua Bridge State Park
Pennsylvania (non-rail) Roads
Back to Non-Roads main page