In choosing a date to mark the beginning of the Renaissance, art historians often seize on 1401, the year Florence’s powerful wool merchants’ guild held a contest to decide who would receive the commission to design the North Doors ★★ of the Baptistery to match its Gothic South Doors, cast 65 years earlier by Andrea Pisano. The era’s foremost Tuscan sculptors each cast a bas-relief bronze panel depicting his own vision of “The Sacrifice of Isaac.” Twenty-two-year-old Lorenzo Ghiberti, competing against the likes of Donatello, Jacopo della Quercia, and Filippo Brunelleschi, won. He spent the next 21 years casting 28 bronze panels and building his doors.

The result so impressed the merchants’ guild—not to mention the public and Ghiberti’s fellow artists—they asked him in 1425 to do the East Doors ★★★, facing the Duomo, this time giving him the artistic freedom to realize his Renaissance ambitions. Twenty-seven years later, just before his death, Ghiberti finished 10 dramatic lifelike Old Testament scenes in gilded bronze, each a masterpiece of Renaissance sculpture and some of the finest examples of low-relief perspective in Italian art. Each illustrates episodes in the stories of Noah (second down on left), Moses (second up on left), Solomon and the Queen of Sheba (bottom right), and others. The panels mounted here are excellent copies; the originals are in the Museo dell’Opera del Duomo (at the east end of the square, on the other side of the Duomo). Years later, Michelangelo was standing before these doors and someone asked his opinion. His response sums up Ghiberti’s accomplishment as no art historian could: “They are so beautiful that they would grace the entrance to Paradise.” They’ve been nicknamed the Gates of Paradise ever since.

The building itself is ancient, but recently restored. It is first mentioned in city records in the 9th century, and was probably already 300 years old by then. Its interior is ringed with columns pilfered from ruined Roman buildings and is a spectacle of mosaics above and below. The floor was inlaid in 1209, and the ceiling was covered between 1225 and the early 1300s with glittering mosaics ★★. Most were crafted by Venetian or Byzantine-style workshops, which worked off designs drawn by the era’s best artists. Coppo di Marcovaldo drew sketches for the over 7.8m-high (26-ft.) “Christ in Judgment” and the “Last Judgment” that fills over a third of the ceiling. Bring binoculars (and a good neck masseuse) if you want a closer look.