Florence must have the greatest density of art you've seen in books of anywhere in the world. The Uffizi (the buildings in the foreground) have a lot of it: Botticelli, Michelangelo, Raphael, Leonardo da Vinci, Titian, etc. etc. etc. etc. etc.... And not lesser works, but The Good Stuff (and displayed in a Medici palace, no less). Apparently the line to get in can be hours long in peak tourist season, but in December, at nine in the morning, there was hardly anyone.