So, in the campaign that I've started in, I rolled up a Kimmerian, and I ended up choosing to be one of the Kimmerians from the ancient isolated underground city of Krimmea, because, hey, ancient isolated underground city.

That said, I didn't find much about the actual location itself, aside from some rough history (isolationists escaping the Green Death, only recently started interacting with the upper world again, secretive, possible otherwordly influences, etc.)

Is Krimmea based on something specific from literature (like Leng, the mythos elements, etc.), or is it something created by the author out of whole cloth?  I know the author likes to keep a lot of this vague so as to be very adaptable to any campaign or style, but I was curious if there was anything more about it out there that might be of interest.

For example: the Krimmeans, are they 'regressed' Kimmerians from all their isolation and limited resources, or do they fancy themselves the 'civilized' Kimmerians from ages ago, still holding to their loftier, more 'cultured' ways apart from the rabble that scamper about topside?  Is it a warren of maze-like corridors stretching for miles, or is it a set of vast, open caverns with spired towers reaching up across the gulf to the ceiling above? etc, etc.

Again, if there really isn't anything more specified about it that's fine too, but as I said previously, I do loves me some lore, so if there is anything out there already, I'd love to take a look.