This brooding fortified church harbours some lovely 13th-century frescoes and a delightful hidden cloister. The frescoes, in the Oratorio di San Silvestro , depict the story of the Donation of Constantine, a notorious forged document with which the emperor Constantine ceded control of Rome and the Western Roman Empire to the papacy.
To access the Oratorio, ring the bell in the entrance courtyard. You might also have to ring for the cloister, which is situated off the northern aisle.
The basilica, which dates to the 6th century, took on its present form in the 12th-century after the original was destroyed by Normans in 1084. Its name – the Basilica of the Four Crowned Martyrs – is a reference to four Christian sculptors who were supposedly killed by Diocletian for refusing to make a statue of a pagan god.
The basilica's frescoed Aula Gotica (Gothic Hall) was recently reopened to occasional guided tours. For details, see www.aulagoticasantiquattrocoronati.it.
