As a kid (11 or 12) me and my friends got lost in the underground drainage tunnels beneath Henderson, NV (a cursory search of said tunnels below Las Vegas, NV will give you an idea how massive these things were.

Billions of tons of dirt over our head. 100, 200 feet upward to the surface. Stuck in a tunnel five feet high by three feet by three feet. It had been two hours since we entered, and we had been walking since.

Our phones, of course, wouldn't work. I myself was freaking out 'cause I was gonna be late getting home...and then I realized...I'm not getting home. Not ever.

No one knows we're here. Even if they did...what could they do? Dig to us? No, no - the predicament we were in was past every adult and the police and the fire department and even the full force of the friggin' feds to solve. What was worse...not only would we die...we would die there and nobody would know about it. Nobody would find our bodies. Nobody would have been trying to save us. Nobody would know if we were even dead. Just...disappeared - like one of thousands do every year.

We eventually ran into a couple - one male one female. Homeless. Junkies. Malnourished. They led us out.

We were lucky because junkies live in drainage tunnels around Las Vegas. They don't around deep cave networks in national parks.