5. The Uffizi Gallery Florence, Italy
www.uffizi.com
Florence is the birthplace of the Renaissance, and if you truly want to understand the history of representational painting to see where artists learned the secrets of portraying man and nature with breathtaking realism you must visit the city where it all began. Highlights include Botticelli's "Birth of Venus" and Leonardo da Vinci's "The Annunciation," not to mention an outdoor cafe that offers a priceless view of the rooftops of Florence.
If you're visiting during the summer tourist season, you'll likely encounter long lines. Circumvent them by calling ahead to make reservations (dial 055294883 when in Italy or add the 39 country prefix when calling from the United States for an English-speaking operator). It costs three extra euros above the ticket price, but you won't be sorry.