They're very local, and only really established in the Forest of Dean in Gloucestershire and in Sussex. They're native but were completely extinct for centuries after being hunted out in the 13th (?) century. Towards the end of the last century they returned through a combination of escapes and not-necessarily-official reintroductions and seem to be doing well enough for themselves.
They can be aggressive if threatened, but these were wandering about basically ignoring humans (and dogs - and this is close to a car park, so there were plenty of both around). They approached pretty close (one wandered up to within a couple of yards while we were stood still watching), but only ever because they wanted to get to a bit of unturned earth you were close to!
That said, I wouldn't have been inclined to risk causing them any stress - they're powerful animals with big teeth...
