Do not adjust your set! That screenshot is proof if ever proof were needed that last-gen games were brown. But anyway, there's actually an Achievement/Trophy for jumping off the tallest tower in the game, which just so happens to be Florence's Campanile, as pictured right here. In all honesty, it doesn't look *that* big while you're stood on the ground looking up (well, alright, it does have birds circling around it), but just wait until you're climbing the damn thing.
And of course, video game characters love to dangle from ledges, which is all well and good when you've got infinite grip, but something in the human psyche says 'hang on (literally), we're a long way up, relying on monkey grip and all the people look like ants. And the ants... well, they're now invisible, wise guy. But hey--you wanted to do this.' But then, the human psyche will also exhibit a strange desire to test that 'Drop' prompt under the B button. Just to see what happens.