Oh gosh - Green Lane baths! That's where I learned to swim. I remember the 'old baths' had changing 'cupboards' all around, with a partition shielding them from general view, apart from the one near the entrance, where the unlucky occupant had to change in view of all the swimmers.
I remember the place always being busy, and having to queue outside for the next session, which were frequently segregated, with boys in the old and girls in the new baths or vice versa. Swimmers were watched over by a dragon in a white coat, who blew a whistle at troublemakers, and who chased you out at the end of the session, often half dressed, hopping along trying to get socks onto wet feet! I got a free pass which, I think, was for passing life saving exams.