In an old hamam there now is a museum informing about the function and culture of hamams, with some fitting displays. This is just an impression. It's at Karagöz, 27400 Şahinbey/Gaziantep, Turkey, entrance is free.
If you've never been in a Turkish bath, this is a good start. And it's fun to see al kinds of soaps, utensils, the lot.