There is still one where I live, and I read the other day that my town is building another one on the other side of town. So at least some places still have them. I remember spending my whole summer at ours in my hometown, but I haven't been to my local one in the 10 years I've lived here. Not sure how I would go about being comfortable to go by myself as a young adult, though I know no one else there actually cares. Nice read by the way.
I spent so much time at our neighborhood pool as a kid. We would get dropped off by a parent and then they'd come pick us up either around dinner time or when a thunderstorm rolled in. Other days, we would go after dinner and stay until it got dark and the pool would close.
I just looked it up, since my hometown had budget issues a few years ago, and it is now owned by the YMCA.