Mm.

[ He still thinks it's overkill, particularly since he hasn't seen anything that made it seem like the ones who made the weapons seemed threatened by the idea of others learning, but he supposes anything is possible. He lifts his arm to hold the lantern a little closer to the wall, frowning in thought. ]

Made. Maybe branched off of natural ones, but the cavern rooms are definitely additions. I'd be surprised if the paths weren't widened.