Oh my god I wonder that a lot, too. I know there are some places in europe where public nudity is quite legal, but I wonder about the legality of open sexual displays where randos are walking by and driving by. Maybe it's just not enforced because the police don't care? Or maybe it's just not taboo in their culture?
There are lots of times and places in the world's history when open displays of sexuality were tolerated or even celebrated. But I just wonder if there are still places today where that is true...
A quora page suggests one park in Amsterdam, but only if it's not around kids and preferably at night - https://www.quora.com/Are-there-any-countries-that-allow-public-sex
I know I read an article a couple decades ago about some cities in Brazil leaving lights on near the beach because they knew young folks were out there banging, and they didn't want muggers to be able to sneak up on the jubilant couples.
Anyone have any other references? This is something that I'm insanely curious about.

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