My buddy always suspected that this was Swede tunnel (also called Beverly tunnel, according to Ed Wolfe in his book on the Interstate Railroad), located at 36.919845, -82.449835 on the Guest River Gorge Trail. I thought that Swede was the tunnel located in Coeburn (see that post), but, thanks to a comment from a viewer, I was corrected. I think this tunnel, the only one on the Guest River Gorge Trail, is about 200′ long. This is looking down the trail.
Blogging the Railroad Tunnels 