They tend to grow over the walls and into view along Deadmans walk (the path where Jews and other non Christians were carried outside the city walls for burial).
They are quite friendly if unlike me you are not a wimp about going upto them (had a bad experience with a horse as a child). They do get cranky when they have foals, but that’s understandable. However it’s usually the cows that chase dog walkers and others. The Horses are happy to munch on grass and drinking water from the Thames.