The Basilica is one of the most important churches of Naples, closed for decades because of the restoration and archaeological investigations. The era of the foundation, on a pre-existing pagan temple, is placed around the year 324. A large reconstruction was in the sixth century, when the Church was included among the four largest of the city. The last substantial transformation occurred through the work by Dionisio Lazzari, called to renovate it in 1656, who designed the exquisite "half-dome" between the nave and transept. In 1689 they were completed Cappelloni of the Crucifix and Saint Lucy. The interior has a typical basilica plant: a nave and two aisles with nine chapels and two big chapels in the transept. Important traces of the nineteenth century ceiling, built after the earthquake of 1870, is in the first chapel of the left aisle. Mutilated by repeated theft occurs, however, the impressive altar by Domenico Antonio Vaccaro, built in 1743 and flanked by two marble balustrades and Roman Corinthian columns in cipolin marble of sixth century. Behind the altar is visible the most obvious trace of the early Christian building: the semicircular apse of the sixth century.