I grew up in the '80s where there's a lot of these kind of post-apocalyptic, post-comet, post-whatever it was, so that always captured my imagination a lot as a little kid, that idea of getting access to secret places and being able to roam around where you're not supposed to.
My mother had always told her kids: if you're about to do something, and you want to know if it's a bad idea, imagine seeing it printed in the paper for all the world to see.