The cathedral was built in the 5th-6th centuries using the remains of a Roman temple with five naves in the cityforum. The building underwent many alterations and restorations, among them those of the 11th century, of the 13th century and above all the extreme restoration in the Baroque style of the 18th century, which reduced the church from five naves to three with the construction of side chapels and the covering over of the Romanesque A-framed ceiling with barrel vaulting. The cathedral was the site of the Papal conclave of 1088 which elected Pope Urban II. , the cathedral is undergoing another restoration.
Description
The portico, which stands at the top of a flight of 30 steps on the podium of the Roman temple, is of artistic interest. It contains six reused Classical columns with a triumphal arch in the centre, surmounted by an ancient entablature with mosaic decorations including the figures of a winged monster, an eagle, palms, deer, birds, bulls and other things. Beneath the portico are a funerary basin of the Roman age and pairs of beasts crouching to either side of the bases of the columns. A further 7 steps lead to the two entrances to the cathedral, of which the principal one is decorated with marble friezes of the Augustan period. To the north of the portico is the Romanesque campanile, curiously raised above ground level on four pilasters. The interior has three naves separated by reused Roman columns, with side chapels. The two side naves terminate in apses, while the central one, terminates in a quadrangular space occupied by the choir. The presbytery and the choir are about a metre higher than the three naves. The following features are of particular artistic interest:
the spiral column, used to hold the Easter candle, of the mediaeval period; a marble inscription gives the maker and the date of the column: Crudele, 31 October 1245;
the 18th-century frescoes of the presbytery and choir, depicting episodes from the election of PopeUrban II.
