James Maleszewski shared a link to this excellent series of pictures today - auctions of the original art from a very old dungeon-exploration themed art book.
This piece, especially, could easily depict the kind of area I put in Felltower:
Don Greer, Gargoyle Guarding the Chamber of Decision, Down in the Dungeon interior book illustration, 1981
It would fit, either with the wizard in the middle or without. "Let's just go 30-40' down each one and then we'll decide which one to explore." Or is it really not that simple? Let's find out.