Have any human societies ever lived underground?

[Warpy]

4. My guess is that they also hid from the occasional bad tempered volcano

and Turkey has quite a few of those.

There is evidence of animal occupation as well as human occupation, so it seems they took everything they could.

Still, the article is correct, they couldn't stay there long, the diet would have been vitamin C poor and vitamin D levels would have dropped fairly quickly. They'd have to get to the surface periodically to soak up some sun and forage.