The Roman remains (including the (not sure if it was the eastern or northern) tower on the pic there) are mostly underground. Some of them have been partially destroyed during the constructions of various monumental projects in the last 1-2 centuries, alas. Only a few, like the part of the city walls on the pic, are partially exposed in an underpass. Though currently there are talks about an overground exposition of a larger part of them (or an underglass one, maybe). Then there's the recently discovered huge amphitheatre, a part of which currently forms a fitness club in a hotel over it. Yeah, I'm disgusted as well...