I picture both Duckburg and Mouseton as largely populated American cities. So, naturally, there would be a lot of skycrapers, towers and high-rise buildings there.
The Money Bin is most often called the highest building in the city. Yet, according to Don Rosa, the bin itself is "only" 40 metres high while Killmotor Hill is several hundred metres high. Rosa also showes "McDuck Tower" which is a mixed-use skycraper and probably the highest building in Duckburg.
Barks' portrayals of The Limpspire State Building, and The Vampire State Building showed them to be taller than any others he pertrayed (that I can remember). There were some tall buildings in his splash panel of Downtown Duckburg in "The Magic Hourglass". The two buildings I listed above were significantly taller than the tallest money bin Barks showed.
I'm glad I don't live in "The Vampire State" (Calisota). We mere mortals would have a very precarious existence in such a dangerous place.
One of Duckburg's tallest buildings is the Rockerduck Building built in glass and reinforced concrete in an attempt to build the tallest building in the whole city. He managed to overcome even the money bin of Scrooge who had to add the final dome to his building to regain the primacy. Currently the building has been surpassed also by the Ducklair Tower an imposing skyscraper of one hundred and fifty-one floors owned by the billionaire Everett Ducklair.