Underdark Cavern - Still Image (Patreon)

I've been meaning to do some more underground locations for a while, and I haven't yet played or ran and Underdark adventure, but I think the setting is super cool. The Underdark, like the material plane, has so many varied environments, but I wanted to do an image that looked reasonably ethereal, but could stand in for a normal cave system, maybe even a mine in this case. 

I would like to do more underground location in the future, so what kinds of locations might you find venturing around the Underdark? Lemme know.