Built from 1383 for the merchant Francesco Datini. It was decorated by Florentine artists like Agnolo Gaddi and Niccolò Gerini. In 1409 it housed Pope Alexander V and Louis of Anjou. Palazzo degli Alberti (13th Century), housing a museum with works by Filippo Lippi (Madonna del Ceppo), Giovanni Bellini (Crucifix with Jew Cemetery) and Caravaggio (The Crowning with Thorns). Castello dell'Imperatore Located in the city center, this is the northernmost castle built by Frederick II of Hohenstaufen in Italy. Main churches in the historical center Prato Cathedral One of the most ancient churches in the city, already in existence in the 10th century. It was built in several successive stages in the Romanesque style. The church contains a number of notable works of art, in particular fine sculpture. Santa Maria delle Carceri Commissioned by Lorenzo de' Medici to Giuliano da Sangallo in 1484. It is on a Greek cross plan, inspired by Brunelleschi's Pazzi Chapel. Works lasted for some twenty years. The interior is run by a bichromatic maiolica frieze by Luca della Robbia, also author of four tondos depicting the four Evangelists in the cupola. The external façade is unfinished, only the western part being completed in the 19th century according to Sangallo's design. Sant'Agostino built from 1440 over an existing edifice from 1271. It has a simple façade with a rose window and a bell tower with pyramidal top. The interior is on the basilica plan, with a nave and two aisles divided by brickwork columns having "waterleave" capitals (c. 1410). The apse chapels date to the late 14th century. The interior is home to canvasses by Giovanni Battista Naldini, Lorenzo Lippi, l'Empoli, Giovanni Bizzelli and others, as well as 14th-century frescoes. The cloister dates to the 16th century. San Domenico The interior altars house a crucifix of the 14th century and an Annunciation by Matteo Rosselli (1578–1650). The cloister of the adjacent convent was built in 1478–80. An adjacent museum has works of wall frescoes. San Francesco It houses a funerary monument of Geminiano Inghirami (died 1460), and the frescoes by Niccolò Gerini in the wonderful Cappella Migliorati. San Fabiano Already existing in 1082. It houses precious traces of a pavement mosaic dating from the 9th–11th centuries. Also notable is the 15th-century bell tower. Minor Basilica of Santi Vicenzo e Caterina de' Ricci Adjacent to the late-Baroque monastery of San Vicenzo. The church was decorated for the