With the tourist barrier and bridge directly behind you, you will see a series of columns with arches on top of them. Counting from the left, go through the opening of the third arch. Ahead and to the left will be a squat cylindrical shape with a lot of narrow columns supporting a conical roof. Go stand next to that.
Walk across the hallway to the other row of columns. Wait next to the circular structure with a roof.
Walk across the very large room towards A rounded structure of stone with a cone-shaped roof, and wait there.