Florence Town Walls
The city of Florence used to be surrounded by high defensive walls. In Dan Brown’s Inferno, the adventures of the main character Robert Langon take place in this city.
The city walls surrounding Florence have been widened and rebuilt over the centuries six different times (although the actual count is controversial) to defend the city, which has undergone various expansions and contractions. Fortunately, solid and impressive remnants of the ancient city walls still survive: the doors (porte) and a few towers.