While the Leaning Tower of Pisa is certainly the most famous tilting tower of Italy (if not world-wide), it is not the only Italian tower that was either intentionally or unintentionally constructed to not stand perpendicular to the ground.
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And 3 of them are in Pisa alone.
The Wikipedia article on leaning towers is more comprehensive and less cancerous: https://en.wikipedia.org/wiki/List_of_leaning_towers