Three noblemen from Benevento, Paldo, Tato and Taso, founded this monastery in 731 near the source of the Volturno river, and by the early ninth century it housed more than three hundred monks, one of the great Benedictine centers of early medieval Europe.
Earthquakes in 848 and Saracen raids in 881 devastated the community, and a new abbey church, consecrated by Pope Paschal II in 1115, rose to replace what was lost. Excavations around the site's Crypt of Epiphanius have uncovered mid-ninth-century frescoes, including an image of the Archangel Raphael, painted before the raids destroyed most of the older monastery. Bombed again in the Second World War, the site now combines an active convent of Benedictine nuns, resident since 2016, with an archaeological area open to visitors, far less visited than Monte Cassino to the south.





