My preference is for American public nudity and that is a lot rarer. The best site for it these days is probably FTV Girls. FTV isn't specifically for public nudity but there is a lot of it and lot of it is pretty daring. If you haven't been a member there before I recommend it.
Another site that is no longer updating but still available is Teasers VOD. Teasers VOD has some of the most daring American public nudity I've ever seen. A couple of warnings though. First, it hasn't updated is at least five years so the video resolution is also pretty low. It is watchable though. Second, after Los Angeles started turning up the heat on these guys they had to turn the heat down. They started producing a series called "The Girls of Porn Valley" or something like that. It wasn't nearly as daring. Soon after that they got a cease-and-desist order from the city that killed them. I recommend checking it out.
There are two sites named Nude in LA and Nude in SF. They may no longer even be available. I found that although there was public nudity it wasn't nearly as erotic and fun as Teasers.
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