Mt. Athos, on the easternmost "leg" of the three-legged Chalkidiki Peninsula in Greece, went from being a sacred place in Greek mythology that was settled variously by Greeks and Macedonians and whoever was living in Eastern Anatolia at various times, to being conquered by the Persians, to becoming a Christian "Holy Mountain" in like the 400s AD under the Byzantines. By the 800s there was a well-established monastic community there, that demanded everyone leave them alone, no girls allowed. And everyone went "okay, cool."
...And that has NEVER STOPPED.
The Ottomans conquered the area but were apparently so impressed with it they vowed to defend it. I guess Russia invaded once, but it was part of some spat between the Greek and Russian church and I think it ended with the monks agreeing to let Russian monks do stuff there. All the wars of dying empires and national independence movements in that part of the world, and everyone else just agreed to leave them alone. When Hitler invaded, the monks asked him to stay away. He said sure.
Modern Greece lets it be a "virtually autonomous region managed by the monks."
There are stories about at least one monk from there who never saw a woman. I don't even get how that's possible. Are they cloning guys up there?
Apparently no one is allowed to find out.
Everyone has eagerly donated lots of money to them over like 1000 years, so God only knows how wealthy they are.
I guess the sea around there is really rough and dangerous so it's not worth anyone wanting to develop it.
I'm sure no gay stuff happens there. Ever.