I have recently (last summer) been to the Laurel Hill Tunnel, with permission, and a guide from the turnpike. The tunnel floor is in pretty bad shape because it had been used for salt storage. The upper parts were in better shape than I had expected, except for on the eastern end. At the eastern portal the roof of the portal building has partially collapsed. The collapse does not appear to have directly affected the tunnel itself. The tunnel was passable, and we were able to drive through it.

I would not suggest attempting to access the tunnel yourself. The upper areas are used as a bat habitat, and the bats are not to be disturbed. The tunnel, as mentioned in another post, is also used to store core samples.

If you wish to learn more about this tunnel, please contact me. I may be able to point you in the direction of some photos, and people. "southpennrailroadpennrailroad" has a CD of photos, which may include photos of this tunnel. See his website at www.southpennrailroad.com for more info.