The roots of Mantua Cathedral date can be traced back to many centuries ago, when the early Christian churches of St. Paul and St. Peter stood in the heart of the old city - then the highest area of Mantua - not far from where Piazza Sordello is situated today. The Church of St. Peter underwent numerous changes over the centuries. It was first a Romanesque church, then a Gothic church, and later rebuilt by Giulio Romano. During the twilight years of his life, Romano transformed the interior, designing a majestic nave and aisles that bear considerable architectural resemblance to Roman basilicas and to the original St. Peter's in Rome. This captivating building was completed with a façade in the 18th century, thereby concealing the late Gothic exterior built by the Venetian brothers Jacobello and Pierpaolo dalle Masegne. The interior houses numerous works of art: a sarcophagus from the 4th century A.D., frescoes and paintings by Antonio Maria Viani, decorative elements by Ippolito Andreasi, paintings by Brusasorci and Girolamo Mazzola Bedoli, tombstones and ancient statues, two magnificent chapels and pictorial fragments from the Gothic and Renaissance periods.