Has anyone explored the entrances to the abandoned and unused tunnels adjacent the PA turnpike?
Update: The PA Turnpike Commission is going to re-align the PA Turnpike at the Allegheny Mountain Tunnel, creating another section of the "Abandoned Pennsylvania Turnpike". This is good news for South Penn RR fans, as we will have another section of where the South Penn RR could've run if Vanderbilt had succeeded in bringing his railroad to southern PA.
A couple of fallacies here. First the western terminus of the South Peen would have been Demmler, near McKeesport, not Pittsburgh. The second is the idea that the turnpike is built on the old South Penn right of way. With very few exceptions it is not. In many places, the remnants of the South Penn can be seen along the highway if you know where to look.
As for the realignment of the turnpike in the Allegheny mountain area, do not assume the abandoned sections of the turnpike are the old railroad right of way. They are not. The railroad would have taken a completely different, and much less steep, route up the mountain. Even the Allegheny Tunnel itself is not the railroad tunnel, which sits abandoned beside the turnpike tunnels.