Banani said:
Anyone with enough brains can teach themself parkour.
Of course you'd need to be fit also.
It's a
LOT of effort without someone experienced teaching you though. In parkour, there are a lot of important techniques you need to know precisely. If you don't do them right or stuff them up, you could potentially end up seriously hurting yourself.
I've seen people die (literally, but not personally), falling from buildings during leaps and such, because they were not aware of what they were capable of, and how to do it properly.
I would encourage everyone to hook up with their local parkour group for training.