I'm thinking medieval Italy myself. Watching "Wolf and Business Talent" at about 16 minutes in I thought I recognized the city of Patzuille. In fact, I've stood at an overlook (the Piazzale Michelangelo) with rails similar to those in the anime.
Here's what I saw. Of course things change in five centuries so it doesn't look quite like the anime.
The city is Firenze Italy, or Florence in English.
At one point I think they even showed the dome of the duomo (cathedral) in the background of the anime. The only thing is that Patzuille is supposed to be a port city which Firenze isn't.