When I was a kid we used to live reasonably near an old Nike missle site in Northwest Milwaukee. The zillion acre site also housed an Army prison. As kids we used to launch model rockets in the vast fields of the now abandoned site & spent a lot of time hanging out there. The old prison was completely empty & nearby residents & the neighborhood kids used to swipe the scrap metals: bronze & brass plumbing fixtures, copper pipes & roof flashing, stainless steel cabinets......anything salvagable.......for spending money. The cops would visit the site occasionally but couldn't do anything about it, after all, they wouldn't climb the pipes between the walls like we could as kids. We'd sit up on top of the prison roof watching as they drive by powerless.

When you're 12 yrs. old or so it felt pretty good!

Anyways, we discovered that the whole site was riddled with tunnels, access tunnels between base housing & the prison, tunnels leading to the missle silos, tunnels all over the place. Some had collapsed, some had been filled in, some just dead-ended, we could never figure out why.

There was one tunnel that was miles long; it lead from a house directly to a giant steel door in the basement of the prison. Back then, to be a "member" of our super secret gang it was required to walk the tunnel in total darkness until you could no longer hear the rest of the kids whisper. Now, that may not seem like a long distance but sound carried through this tunnel like nothing you'd believe. If there were a group of kids behind you it was possible to hear them whispering long before you see the light from their flashlights. The tunnel was damp, you'd hear dripping water, fairly high, at least for a kid & had several dog-legs in it so, after a while, you'd lose track of what direction you were walking. And it was a direct tunnel, no additional tunnels intersected with it. I'll tell you, walking through an unknown stretch of tunnel with no lights is an exercise that spooked the bejeebers out of us. None of my friends EVER went into The Tunnel without a fresh set of batteries; being stuck somewhere in the middle of the tunnel was just about the worse nightmare any of us could think of. We joked about it often!

The Nike silos were useless; they had been filled in or were in such disarray that even as kids we knew better than to explore them. Metal sticking out everywhere, ladders bent out of shape: useless.

Seeing those pictures of the tunnels in PA brought back some memories.......

The entire site is now preserved as a natural space; I think it's called Havenwoods nowadays. As far as I know all the old buildings including the prison are long gone.
But I wonder if some of the tunnels are still there..............