| Basilica of Saint Petronius | |
| Native Name: | Italian: Basilica di San Petronio |
| Location: | Bologna, Italy |
| Coordinates: | 44.4928°N 11.3436°W |
| Religious Affiliation: | Catholic |
| Province: | Archdiocese of Bologna |
| Status: | Basilica |
| Functional Status: | Active |
| Architecture: | yes |
| Architecture Type: | Church |
| Architecture Style: | Italian Gothic |
| Groundbreaking: | 1390 |
| Capacity: | 28,000 |
The Basilica of San Petronio is a minor basilica and church of the Archdiocese of Bologna located in Bologna, Emilia Romagna, northern Italy. It dominates Piazza Maggiore. The basilica is dedicated to the patron saint of the city, Saint Petronius, who was the bishop of Bologna in the fifth century. Construction began in 1390 and its main facade has remained unfinished since. The building was transferred from the city to the diocese in 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.
In 1388, the Consiglio Generale dei Seicento prepared the construction of the church as a civic temple.[1] To make room for the church, the adjacent Curia of Sancti Ambrosii was demolished, together with the majority of one of the city's burgs, including at least eight churches and towers. The first stone of construction was laid on 7 June 1390 under the supervision of architect Antonio di Vincenzo. 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.
The third bay was built in 1441–1446. Its construction was delayed by the cardinal Baldassarre Cossa, who sold the construction material of the basilica and kept the money.[2] In 1514, Arduino degli Arriguzzi was chosen as the architect to construct the dome. His proposal included a large dome resting upon the width between the side aisles, which necessitated larger transepts and apses.[3] The project was considered too complicated, and after building the first two pillars and two triangular pylons for the dome, the work was halted. According to legend, Pope Pius IV halted the "megalomaniac dream" and instead encouraged the construction of the Archiginnasio of Bologna.
The basilica is a large church measuring 132 metres long, 66 metres wide, and 47 metres tall, and is described as the "most imposing" church in Bologna. The facade was designed by Domenico da Varignana and started in 1538 by Giacomo Ranuzzi. However, it remains unfinished.
The main doorway (Porta Magna) was decorated by Jacopo della Quercia of Siena with scenes from the Old Testament on the pillars, eighteen prophets on the archivolt, scenes from the New Testament on the architrave, and a Madonna and Child, Saint Ambrose and Saint Petronius on the tympanum. It is flanked by two side doors, with Alfonso Lombardi's Resurrection on the left and Amico Aspertini's Deposition on the right.
The central nave covering and apse shooting were completed in 1663, designed by Girolamo Rainaldi and directed by Francesco Martini. The lower naves are enclosed by rectilinear walls. The first two windows were designed by Antonio with the assistance of Francesco di Simone, Domenico da Milano, Pagno di Lapo Portigiani and Antonio di Simone. The bell tower was designed by Giovanni da Brensa and built between 1481 and 1487.
The interior houses a Madonna with Saints by Lorenzo Costa the Younger, and a Pietà by Amico Aspertini.
The altar contains a 15th-century wooden crucifix. At the back, a fresco of the Madonna with St. Petronio by Marcantonio Franceschini and Luigi Quaini, cartoons by Cignani (1672). The ciborium of the main altar was built in 1547 by Jacopo Barozzi da Vignola.
The fifteenth-century wooden choir was completed by Agostino de 'Marchi. The vaulting and decoration of the central nave is by Girolamo Rainaldi, who completed them in 1646–1658.
The nave contains twenty-two side chapels:
Bologna was a principal centre of Baroque music in Italy. The musical organisation 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 by Lorenzo da Prato and 1596 by Baldassarre Malamini, both still in remarkably original condition; the library remains a rich archival repository. Three successive maestri di cappella marked the great age of music at San Petronio: Maurizio Cazzati (1657–71), Giovanni Paolo Colonna (1674–95) and Giacomo Antonio Perti (1696–1756).[4] The current maestro, since 1996, is the harpsichordist Sergio Vartolo who has revitalised the cappella with a series of recordings for Naxos, Tactus, Brilliant Classics and Bongiovanni.
The church hosts also a marking in the form of a meridian line inlaid in the paving of the left aisle in 1655; it was calculated and designed by the astronomer Giovanni Domenico Cassini, who was teaching astronomy at the University. A meridian line does not indicate the time: instead, with its length of 66.8m (219.2feet) it is one of the largest astronomical instruments in the world, allowing measurements that were for the time uniquely precise. The sun light, entering through a 27.07mm hole placed at a 27.07m (88.81feet) height in the church wall, projects an elliptical image of the sun, which at local noon falls exactly on the meridian line and every day is different as to position and size. The position of the projected image along the line allows to determine accurately the daily altitude of the sun at noon, from which Cassini was able to calculate with unprecedented precision astronomical parameters such as the obliquity of the ecliptic, the duration of the tropical year and the timing of equinoxes and solstices. On the other hand, the size of the projected sun's image, and in particular its rate of variation during the year, allowed Cassini the first experimental verification of Kepler's laws of planetary motion.
Cassini and Domenico Guglielmini published an illustrated account of how the meridian line was accomplished in 1695.[5]
In 2002 five men were arrested on suspicions of planning to blow up the basilica. The men were allegedly connected to Al Qaeda.[6] [7] Again in 2006, plans by Islamist terrorists to destroy the Basilica were thwarted by Italian police. The terrorists planned to destroy the church because one of the chapels features a 15th-century fresco, painted by Giovanni da Modena and based on Dante Alighieri's Divine Comedy, depicting Muhammad in the eighth circle of Hell, in a section reserved for religious schismatics, being tortured and devoured by demons.[8] [9]