Yeah, I did that a lot, back in those days. It seems impossibly risky now. But when you're young, you feel immortal. And conversely, we were all expecting to die in a global nuclear war. So hey.
I was a five-year-old in Eugene, Oregon in the late 1950s. The new house being built down the hill next door had an underground bomb shelter. Of course we made that our clubhouse during construction!
The house just up the hill wasn't as far along, but they had cut down the trees and we made tunnels and hideouts among the fallen trunks and branches. We called it "The Rough Country".
And then I got a chemistry set! The real kind, with chemicals and apparatus that could burn you, blind you, or take your skin right off.
Of course, now we have eliminated all risk and the world is perfectly safe.