Google Maps is awesome. I was very puzzled when I was in Montreal that I would look stuff up on Google maps and go to the street location only to not find the shop etc there. It took me a while to work out that a lot of buildings in the Montreal CBD had shops and other businesses in their basements. When in doubt, look down. I might have to go check out the Via Appia though. Did you watch Mary Beard's series about the Romans when it was on here?