In the grotty little Northern town where I had the misfortune to attend primary school, I formed my dislike of public urinals.
The Toilet building was outside the main school - making it a favoured excuse for leaving the classroom - and was clearly developed some time after Norman the Conker had finished with Robin of Sherwood or something. It had a small open area at what I guess would be 4ft high or so, directly above the urinal trough.
This was vaguely reminiscent of the arrowslits in a Castle; something which was not lost on the minds of the older boys, and walking past the building too close became a piss-soaking lottery for the unaware.
However, this was nothing compared to the risks of going inside when a novice was making their first attempt at glory...