Florence

Florence, the cradle of the Renaissance, packs more masterpieces per square kilometer than any rival Italian city—3 million annual visitors to the Uffizi Gallery alone. Brunelleschi's Duomo, completed in 1436, and Michelangelo's David define its compact UNESCO core. Unlike #1 Rome's sprawling ancient sites, Florence's walkable center lets you move from the Duomo to the Uffizi in five minutes, offering a concentration of 15th-century art unmatched even by #2 Venice's Palazzo Ducale.