FKK in the GDR

I created a group about Nudism (FKK) in the former GDR (DDR / Deutsche demokratische Republik). I search for members wo can say something about it. Why were so many people naked at the beaches? Where else were they nude? And why it stopped after the reunification of Germany? Please tell us your experiences and opinions about it. And not least put your pictures of the nude life in the GDR in the media.