I suppose all of us have stood next to the colosseum and looked up the slope towards the arch of Titus, at the entrance to the forum. Du Perac, in 1575, did the same. His illustration of the scene shows the arch of Constantine to the left, as it still is (the colosseum is immediately to the left, out of view); before it, the vanished “meta sudans” (the concrete core of which appears in 1922 photos, before being demolished by Mussolini as part of a traffic widening scheme), and to the right, the view to the arch of Titus, still embedded in the remains of the medieval Frangipani fortress, exactly as the later cork model shows it.
Click on the image for the full size image (from the BNF in Paris).
It’s interesting that somehow the scene, with walls indicating people’s fields and property, is more “real” somehow than the rather institutional view that one gets today.