What may be most remarkable about this feat of Roman architecture to American eyes might be just how accessible the walls are. We are fussy about our history, perhaps we haven’t as much of it as others. In Istanbul today, the Theodosian walls are as much part of the city as surrounding roads and homes. It’s not uncommon to see an alcove or former garrison quarters being used as a garage or storefront. In one case, a newer residence has been built right into a section of the wall.