If you are stuck in a tunnel with an incoming train, how safe would it actually be to slide up against the wall? originally appeared on Quora, the place to gain and share knowledge, empowering people to learn from others and better understand the world. You can follow Quora on Twitter, Facebook, and Google Plus.

If you are stuck in a tunnel with an incoming train, how safe would it actually be to slide up against the wall?

I have actually done this, and you can too - if you are willing to take your life into your hands.

In western Massachusetts, in the town of Florida, is the Hoosac tunnel, one of the longest active train tunnels in the US. It’s five miles long, hundreds of feet under the Berkshire Mountains. It was started in 1851 and took almost 25 years to dig and was nicknamed the “Tunnel of Blood” because of how many men died digging it.

The Hoosac Tunnel is a single track freight rail system. The rock around the tunnel is so hard that the tunnel was dug very close to the dimensions of the train. For that reason it is extremely dangerous to enter the tunnel. Nevertheless, my friend and I decided to hike through it.

Note that if you do hike the tunnel you should wear good hiking boots and you must have at least two flashlights, and it’s a really good idea to bring water and a sweater. You absolutely must not ever be caught in the tunnel without light - it’s a recipe for a broken ankle or leg. It’s illegal to enter the tunnel for good reason. The train, when it passes, passes so close to the walls of the tunnel that there are little gouges in the rock where you have to throw yourself and stand up straight to keep the train from hitting you. It’s no joke that if you stuck your arm out the train would easily tear it off as it passes.

It’s a remarkable thing that once you enter the tunnel you notice that the air is dead. The deeper you go, the darker it becomes. There is absolutely no source of light and you cannot see anything at all. It’s eerie. There are no birds, or rats, or bats, or insects in the tunnel. There is no trash in the tunnel. Absolutely nothing grows once you’re past the light. Once you get beyond the point where you can see the light from the entrance you are in an entirely different, entirely dead and dark world. The air is cold and dead and damp. The deeper you go, the harder it is to breathe. You would think that something the size of a train tunnel would allow the passage of plenty of air but you would be wrong. The air is still, cold and dead.

Every half a mile or so there is a tiny 10 watt electric bulb on the wall. After the sight deprivation you experience in the dark, that little bulb stands out like a searchlight. It lights a little wooden box with a glass front and a telephone that’s placed there for emergencies. The phone has no dial. As soon as you pick it up, it rings at the stationmaster’s location and they know you’re there. Don’t open the door of the phone box or pick up the phone. If there really was an emergency the phone would be critical.

At the halfway point, a large room is gouged out of the tunnel. The homeless drug addicts who use it in the winter call it the “Hoosac Hotel”. It’s a room where at one time electrical conduits and junctions came together but now it’s largely empty except for abandoned sleeping bags, empty booze bottles, plastic bags, fast food containers and the detritus of despair. On the other side of the track at that point is a tunnel in the ceiling that goes hundreds of feet to the surface. During the time it was made, the air in the tunnel was insufficient to run the fires of the locomotives and supply the people with enough air to breathe, so the ventilation shaft was carved to allow train smoke to vent out and for air to come into the tunnel.

On the way back out of the tunnel, we noticed a light in the distance. It was tiny, like a pinprick, but it flashed like an orange star. It could only be one thing, and setting a foot on the track confirmed what we knew. A freight train was coming. Even hustling as fast as we could, we knew we’d never make it to the entrance of the tunnel. I estimate the train was going 25 miles an hour. It was both terrifying and exciting waiting for that monster to arrive. As it got closer, the ground and the tracks started to rumble and shake. By then we were both running for the gouged-out man traps in the sides of the wall. If you want a death-defying activity that will get your heart going for an extended period, then this is for you. When the train is going by it’s like the world is coming to an end. It’s very, very close to your face, or at least it seems that way. You can’t really look at it - it’s dark once the light of the locomotive passes you by. But you can feel the world shake and hear the screaming rumble like the world is coming to an end and you can smell the stink of diesel. You can feel the cold, grimy wind buffeting you in the little gap and you lean further back. There’s nothing to grab onto but the cold, hard rock you can’t even see. You’re completely blind. Every now and then a steel wheel will throw up a spark from the track; it’s gone in an instant. And it goes on for a long, long time. The freights that use the Hoosac are often long and filled with varied loads. And when it finally passes and you stagger out of the man trap, you’re gagging from the diesel, which really has nowhere to go. It’s a mind-numbing experience.

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