I am looking for some inspiration: dungeons that are mostly natural rather than constructed. Caves rather than castle.
I'm okay with a little modification, like camps or structures built in it, but the foundation should be something naturally occurring (or something that could pass for natural, even if it was created by magic or gods or what have you)
Candlestone Caverns is a prime example of the sort of thing I'm looking for.
Please and thank you!