The Basilica of San Petronio is the main church of Bologna, the old città d'arte in the Emilia Romagna region of Italy; however, it is not the metropolitan cathedral of the city, which is the Cathedral of Saint Peter. It dominates the Piazza Maggiore. It is the fifth largest church in the world, stretching for 132 meters in length and 60 in width, while the vault reaches 45 meters inside and 51 meters in the facade. It can contain about 28,000 persons.
It is dedicated to the patron saint of the city, Saint Petronius, who was the bishop of Bologna in the fifth century. Following a council decree of 1388, the first stone of construction was laid June 7, 1390, when the town council entrusted Antonio di Vincenzo with raising a Gothic cathedral.
Works lasted for several centuries: after the completion of the first version of the facade, in 1393 the first pair of side chapels were begun. The series were completed only in 1479, however. In 1514 Arduino degli Arriguzzi proposed a revised plan in the form of a Latin cross with the intent to outdo even Saint Peter's Basilica of Rome, the greatest church of the Western Christian world even in its ancient version. By tradition Pope Pius IV halted such a majestic project.
In spite of this setback the basilica continued to enjoy the great prestige it engendered from the very beginning: pope Clement VII chose it for the coronation of Charles V in 1530. Jacopo Barozzi da Vignola was chief architect of the fabbrica; his is the design of the ciborium over the altar. The vaulting and decoration of the central nave is by Girolamo Rainaldi, who completed it in 1646-1658.
The facing of the main facade, however, remains unfinished: many architects (notably Baldassarre Peruzzi, Vignola, Andrea Palladio and Alberto Alberti) were commissioned to propose solutions for it, but a definitive one was never found. Jacopo della Quercia of Siena enriched the main doorway with sculptures (illustrated, left) and two new small flanking doorways, with subjects taken from the Old Testament, forming a traditional prelude to the new dispensation that is represented by the basilica itself. The heroic nudes of Adam and other figures in the rectangular bas-relief panels were an inspiration to artists of the Renaissance.
The construction of the basilica was a project of the comune of Bologna, not of the bishops: the property was a symbol of communal power that was not transferred from the city to the diocese until 1929; the basilica was finally consecrated in 1954. It has been the seat of the relics of Bologna's patron saint only since 2000; until then they were preserved in the Santo Stefano church of Bologna.
The interior is notable for a Madonna with Saints by Lorenzo Costa the Younger and a Pietà by Amico Aspertini. Also the colours of the walls and the stained glass windows are noteworthy. The choir was made in 15th century by Agostino de' Marchi, while the ciborium is a work by Vignola.
Bologna was a principal center of Baroque music in Italy. The musical organization had been officially instituted by Pope Eugenius IV in 1436; the first regularly paid instrumentalists were added in the late sixteenth century, and in the seventeenth century San Petronio was renowned for its sacred instrumental and choral music, with its two great organs, completed in 1476 and 1596, both still in remarkably original condition; the library remains a rich archival repository. Three successive maestri di capella marked the great age of music at San Petronio: Maurizio Cazzati (1657-71), Giovanni Paolo Colonna (1674-95) and Giacomo Antonio Perti (1696-1756).[1]
The church hosts also a sundial in the form of a meridian line inlaid in the paving of the left aisle in 1655; it was calculated and designed by the famous astronomer Giovanni Domenico Cassini, who was teaching astronomy at the University: at 66.8 meters it is the longest sundial in the world, following measurements that were for the time uniquely precise; Cassini and Domenico Guglielmini published an illustrated account of how the meridian was accomplished in 1695.[2]
Elisa Bonaparte, Napoleone Bonaparte's sister, is buried here.
In 2006, plans by Muslim terrorists to destroy the Basilica were thwarted by Italian police. The terrorists claimed that a 15th-century fresco inside was insulting to Islam. The fresco, painted by Giovanni da Modena, represents a scene from Dante Alighieri's Inferno, and depicts Muhammad in Hell being devoured by demons.[3][4]