This reminds me of the Temples of Humankind, where a new-age community in Italy (possibly an abusive cult looking at their Wikipedia page) dug in a mountain for

This reminds me of the Temples of Humankind, where a new-age community in Italy (possibly an abusive cult looking at their Wikipedia page) dug in a mountain for a couple decades without planning permission but by the time they were discovered they were impressive enough that they were allowed to keep them. https://en.wikipedia.org/wiki/Temples_of_Humankind https://en.wikipedia.org/wiki/Temples_of_Humankind Looking for them again I also found Sassi di Matera: https://en.wikipedia.org/wiki/Sassi_di_Matera https://en.wikipedia.org/wiki/Sassi_di_Matera