Rome is studded with cannon balls (2022)

Maybe a bit of an exaggeration, but there was a time when Italy was the world’s Middle East (a collection of divided states where the great powers had their proxy wars)

Not a surprise to see Rome have so many based on that.

Stockholm also has famous canon balls lodged on buildings in the old town: https://www.atlasobscura.com/places/stortorget-cannonball

They are supposed to be from the Blood Bath that happened there in the 16th century when Swedes and Danes still enjoyed killing each other frequently, but no wall survives this long with a metal ball in it, hence that’s apparently a fake thing by some smart 18th century building owners.

Fort Pulaski in Savannah, Georgia also has cannonballs embedded in the brick walls: https://en.wikipedia.org/wiki/Fort_Pulaski_National_Monument

Or Rome is the set of a real-life Truman Show.