From the Introduction:
A large mostly dark room lies in front of you. A single bonfire in a pit at its center spreads almost as much smoke as light. Beyond the columns around the outer perimeter of the room passages lead into dark side wings to either side of you. On the other side of the room, straight ahead of you a solid door with two rather intricate locks bars the way deeper into the dungeon.
Like in the rooms you have left behind, the walls are built from solid granite blocks, set so finely that hardly even a sheet of paper would fit between them. Again numerous columns built from the same stone help distribute the enormous weight of the rock above. Only the bonfire lights the central room, while the rooms in the side wings have lamps of their own.