In 1456, the Medicis sent their troublesome but favored artist Fra Lippo Lippi to Prato to paint frescoes behind the main altar of the cathedral. Chronically broke, the friar had just been imprisoned in Florence on swindling charges (allegedly trumped up) and he spent the next 12 years working on what is widely considered his finest work.

The Main Chapel Lippi’s luminous and wonderfully evocative masterpieces depict events in the lives of St. Stephen, the first Christian martyr and the town’s patron, on the right as you face the paintings, and John the Baptist, on the left. The panels are arranged so episodes from similar periods of the saints’ lives face each other across the chapel—birth and youth at top, famous saintly moments in the middle, and death at the bottom. Looking at the panels it’s important to remember that Lippi often merged several episodes from the saints’ lives into a single scene. Handsome young Stephen lies on his funeral pyre in a medieval church, enjoying peaceful eternal rest, while intruding onto the edge of the scene is a rocky outcropping in which the saint is being stoned. In Lippi’s emotional and colorful scenes of John’s demise, the artist portrays a medieval banquet; as the famous story goes, the ruler Antipas tells his stepdaughter, Salome, that he will grant her any wish, and at the prompting of her mother, Herodias, the girl requests the head of St. John on the platter (the saint had proclaimed that the marriage of Herodias and her current husband, a descendant of King Herod, was incestuous, and she was out for revenge). It’s all here—John being decapitated; Salome presenting the head to her mother (who looks vaguely bemused, while the revelers around her seem quite unconcerned by the presence of a severed head intruding upon their revelries); and, of course, the famous dance of Salome, portrayed as a radiant beauty in medieval garb modeled on the nun Lucrezia (who bore two of Lippi’s children, including the likewise-talented painter Filippino Lippi). An especially touching scene in the top panel depicts young John taking leave of his aged parents, Elizabeth and Zecharaiah, as he sets off to live in the wilderness and preach the word of God.

Capella di Sacra Cintura (Chapel of the Girdle) The cathedral is the repository of one of Christendom’s most important relics, the girdle of the Virgin Mary. As the story goes, colorfully told in luminous frescoes by Angolo Gaddi, the girdle was found in the tomb of St. Thomas and became part of a dowry of a young woman in Jerusalem who married Michele Dagomari, a merchant from Prato who fought in the First Crusade at the end of the 11th century. Returning to Prato (quite recognizably depicted in one of the panels). Michele gave the girdle to the church, which, as word spread, became an important site of pilgrimage for pregnant women—as it still is. The chapel was built soon after to house the relic, which is brought out for display five times a year, from a pulpit projecting from a corner of the exterior of the cathedral—on the Feast of the Assumption (Aug 15); the birthday of the Virgin (Sept 8); Christmas Day; Easter; and May 1, the beginning of the month of the Virgin. At other times of the year the girdle resides in a white-gold casket beneath a statue of the Madonna and Child by Giovanni Pisano, best known for his sculpted pulpit in Pisa’s cathedral . The pulpit is a reproduction; the original is in the adjacent Museo dell’Opera del Duomo, allowing you to see close-up the graceful dancing figures that Donatello, who left so many sculptures behind in Florence, carved between 1428 and 1438.

Cappella dell'Assunzione (Chapel of the Assumption) Frescoes in this tall, vaulted chapel near the altar are by Paolo Uccello and the less gifted Andrea Manzini, who in 1435 were commissioned by a wealthy weaver and merchant to paint scenes from the lives of St. Stephen and the Virgin Mary. When you look at the paintings, pay close attention to those by Uccello, and especially his depiction of architecture and use of perspective. The artist was an ardent student of both, and was allegedly so obsessed with perspective that he spent his sleepless nights trying to determine vanishing points in the spaces around him. In the “Disputation of St. Stephen,” the saint stands in front of a dome, a reference to Brunelleschi’s just-completed dome for Santa Maria del Fiore Duomo in Florence, a hot topic in 1436, when the dome was topped off and the frescoes were painted. The saint is arguing his case with authorities who bear uncomfortable resemblance to 14th-century merchants of Prato, finely turned out in luxurious capes and fur-trimmed hats. A keen-eyed architectural historian can pick out more works by Brunelleschi in “The Stoning of Stephen,” where thuggish rock-throwers (by Uccello’s co-artist) stand in front of Uccello’s fascinating group of towers, loggias, spires, and a Brunelleschi-like dome. The “Birth of the Virgin” and “Presentation of the Virgin at the Temple” are also crowded with architectural elements and executed with complex perspective that lend the scenes of color-rich, almost whimsical characters their dramatic intensity.