Note, those pictures depict the towers as about 5x bigger than they actually were.
To get a true sense of scale, here's the same view on Google Earth: https://earth.google.com/web/@44.48152905,11.33820409,94.604... You can see the towers that are still standing. They visibly stick out from the shorter buildings, but they're nowhere near as big as in the picture.
I think Google Earth might be more wrong than the illustration. One of the two Towers of Bologna is 97m. On GE it looks less than that. 97m is more than 33 stories.
I think everything in the illustration is at least twice too high. The walled part of Bologna was ~1 km in diameter at that time, and the tallest towers were ~10% of that.
Why do people attempt to use "stories" as a measurement of height? There is no universal agreement for what a "story" is. 97 meters is in fact 97 meters.
which is also not normalized. A referee once told me that - in theory - football fields can be square. I think it was 80m x 80m since 80m is the minimum length and the maximum width. Correct me if I am wrong.
Field size for American football is definitely standardized: 100 yards between goal lines and 160 feet wide. Lots of Americans will have an intuitive sense for how long something like "three football fields" is.
But that intuitive size would in fact be wrong. The size we associate with an American football field is more commonly going to be the distance including the end zones.
Going to play the pedantic card and mention that there's also no universal agreement on how to measure a building's height. The Council on Tall Buildings and Urban Habitat on its own has three different methods and not everyone accepts those as being the correct and true way of measuring the building's height.
Really? I zoomed in on the Towers of Bologna and then used the "measurement" tool to draw a 97m line on the ground. The line seems about as long as the tower is high. If you try that, do you get the same result?
To get a true sense of scale, here's the same view on Google Earth: https://earth.google.com/web/@44.48152905,11.33820409,94.604... You can see the towers that are still standing. They visibly stick out from the shorter buildings, but they're nowhere near as big as in the picture.