There's a corner of a London park where I sometimes pee in the trees, and I have seen others go in there too. One evening in the summer I went in there but there was a guy there. I was about to turn round and go back out when he said, "it's ok you can wee here, we are having a wee too". I realised there was a woman in there too a bit further back, squatting with her knickers down and in full flow. So I stayed and had a long wee up a tree , with the pair of them weeing a short distance away.