From the Urban Explorers site:
We like to explore abandoned or unused buildings, structures, caves, tunnels, etc. Sometimes, we infiltrate occupied spaces which are ordinarily off-limits to the public.
Wherever we go, we take nothing and we break nothing. Sometimes we may move something, but then we replace it. We leave a site in the same condition that we found it.
Our motto is: "Take nothing but pictures, leave nothing but footprints."
Some locations are dangerous. There can be pollution or physical hazards. You could be injured. If you go on someone else's property without permission, you could be cited by the police or arrested. Nobody connected with this web site is advising you to do anything illegal or dangerous. If you do so, it is your choice, and you agree to take responsibility for your own actions.
Are you kidding me? A grown-up Mark Twain adventure club in my own back yard, and it's taken me this long to discover it? Anytime "explore," "infiltrate," "pictures," "hazards," "arrested," "illegal," and "dangerous" appear in the same job description, that objective really doesn't have a chance. It'll just have to resign itself to being a freaking great hobby.
Aidan and Asher have been tugging on my pants leg all morning with knives between their teeth, begging me to take them on the next Urban Explorers expedition. I wonder if there's a recommended minimum height...