Where I live there are two huge textile mills which have been left to go to rack and ruin. It would be fascinating to see the inside of them
Go have a look, if trespass is not illegal in your country.
EDIT: I see you are from the UK, and the north.. so free game.
Sadly, the mills are off limits to the public with barbed wire to keep people out. Recently, a group of travellers stayed a few days inside one of the mills and were served with a court order to leave!
That's where your legs come in handy. Use them to vault over the wire and start your trespassing career with a bang!