Mines of Robigus: This is my own thinking for what the mines look like–a few large chambers, endless tunnels and a secret or wizard locked entrance to a Roman Temple ruins (of Robigus). There would be large caverns for the Roper lair (glittering cave) and Myconid Fungal Forest lair along with an underground lake and stream running thru the complex. A real labyrinth, of course! Actually somebody could do a decent dungeon based on this Tombs of Atuan map!
Very Celtic.
Clearly, Ged had never heard of the left-hand rule.
Fasil