San Paolo is a church built in 748, and remade in the 12th century, although only in the 14th century it obtained the current forms. The exterior is characterized by a typical Tuscan blend of Romanesque and Gothic styles, with a polychrome decoration of the façade. Over the portal is a statue of St. James, attributed to Orcagna.

The interior has been largely turned into a Baroque one in the 17th and 19th centuries. Works of arts include a fresco with St Agatha and St Eulalia by Gerino Gerini (painter), a 14th-century crucifix and Holy Conversation by Fra Paolino, which portrays Girolamo Savonarola as St. Peter the Martyr. The sacristy has several 14th-15th-century frescoes.