The Cathedral of Siena is undoubtedly one of Italy’s most impressive examples of Romanesque-Gothic architecture, rivaling, and perhaps even surpassing, the famed Cathedral of Florence in its splendor.

From the outside, the Cathedral of Santa Maria Assunta dazzles with its striking facade of black and white marble and 19th-century mosaics by Alessandro Franchi. Inside, its true grandeur is revealed, especially through the marble-inlaid floor, featuring 56 unique mosaic panels — some fully uncovered only during the summer months.

One of the must-see highlights is the climb to the Panorama Platform on the Facciatone, offering breathtaking views of Siena and the Tuscan countryside. Also fascinating are the crypt, hidden for centuries and rediscovered in 1999, with its 12th-century frescoes, and the Piccolomini Library, adorned with Pinturicchio’s frescoes illustrating the life of Pope Pius II.

It’s hard to believe, but the cathedral was once intended to be even larger. However, these ambitious expansion plans were halted by the outbreak of the plague.

The cathedral also boasts some of the most important artworks in history:

• Nicola Pisano’s pulpit (1265–1268) is a sculptural masterpiece, bridging the Gothic and early Renaissance styles.
• Michelangelo, one of the Renaissance’s greatest artists, created 4 sculptures for the Piccolomini Altar, including a possible self-portrait as St. Paul and a striking depiction of St. Peter.
• Donatello’s bronze statue of John the Baptist, housed in the Chapel of John the Baptist, displays his signature dramatic style, capturing the saint in a deeply emotional pose.
• Gian Lorenzo Bernini, the leading Baroque sculptor, is featured in the Chigi Chapel with two exceptional works: St. Jerome and Mary Magdalene in Ecstasy. Sculpted between 1661 and 1663, these marble figures showcase Bernini’s unparalleled ability to convey deep emotion and movement. The Chigi Chapel itself, commissioned by Pope Alexander VII, is an outstanding example of Baroque art.