If you are crossing the aqueduct courtyard bridge you may notice that there are four braziers, two on each side of the bridge. If you light the braziers with a fire spell, you will find that they can be rotated and there are numbers one to four in roman numerals printed around the edge but the rest seems a mystery!
If you look below each of the braziers, on the wall to the side of the bridge, there are unique icons printed into the metal plates here. These are a clue but what do they mean? I tried a bunch of different things until eventually figured it out.
The solution is nothing to do with what is on the plates themselves, you just need to find the cipher, which is hidden near one side of the bridge on what looks like a manhole cover.
All you need to do now is return to each of the braziers and rotate them, once lit, to whatever the matching number is. Once you have rotated all of the braziers to the correct number, the panel on the floor that gave you the clue will open up and you will be able to climb down to the area below for your reward.
