Staple Bend Tunnel - Allegheny Portage Railroad National Historic

Allegheny Portage Railroad National Historic Site, STAPLE BEND TUNNEL

Park Archives: Allegheny Portage Railroad National Historic Site

Exploring the trails of the National Parks of Western Pennsylvania - Allegheny Portage Railroad National Historic Site (U.S. National Park Service)

Allegheny Portage Railroad - Wikipedia

Road Trippin' PA: Staple Bend Tunnel

Allegheny Portage Railroad - Explore Altoona

Allegheny Portage Railroad National Historic Site, STAPLE BEND TUNNEL

Park Archives: Allegheny Portage Railroad National Historic Site

Allegheny Portage Railroad National Historic Site, Raven About The Parks

Staple Bend Tunnel - Allegheny Portage Railroad National Historic Site (U.S. National Park Service)

Exploring the Staple Bend Tunnel in Cambria County - PA Bucket List

Allegheny Portage Railroad Historical Marker