The Abbey was declared a national monument in the middle ages one of the religious and cultural centers of Southern Italy. It was founded by s. Alferio Pappacarbone, who retired in 1011 in Sahib under the great Arsiccia cave, to take life, hermit was induced by flock of disciples to build a small monastery with a small church. Expanded and converted into a basilica with multiple aisles at the time of the Abbot of St. Peter (1079-1123), the Abbey was released from the local scope, placing himself at the head of a large monastic Congregation (Ordo Cavensisis). In 1394 Pope Bonificacio IX the elected to the bishopric, putting it at the head of a diocese. The current basilica was erected in 1761 at the initiative of Abbot d. Giulio De Palma and arch design. John Daniels. The Interior, especially after the modern wall covering and flooring with polychrome marbles, is bright and harmonic. The ancient basilica, in addition to the marble Ambo in cosmatesque style of the 12th century, are two chapels on the altars are arranged precious sculptures by Tino da Camaino, run by the Abbot and Royal Adviser Philip de Haya: the first chapel on the left, presenting an eleventh-century antependium, is a relief depicting the madonna with child between St. Benedict and s. Alferio presenting to our Lady the Abbot de Haya; on the altar of the second chapel on the right, are the two groups of women and of Roman soldiers at the foot of the cross. Soon after, four walls balustrade marble statues among which noteworthy are those of sixteenth century s. Felicita and San Matteo. Proceeding, on the right is the cave of s. Pedro, with the URN that holds the relics, left the altar of s. Leone with his bowl and, on the wall, other relics of Saints. The frescoes of the basilica are the work of the Calabrian painter Vincenzo Morani, who in 1857 there was on the vault of the choir "s. Pedro in contemplation of SS. Trinità"; in the dome a vision of the Apocalypse; in the right transept is the "death of St. Benedict"; left the "Resurrection" with prophets and Apostles. Under the altar of the basilica are 12 laid the relics of the Holy Abbots 12. Next to the Church is a fountain built in 1772 by Thomas Lamb. The small cloister of XI-XIII centuries, although small scale, is the most striking and characteristic of badia: although it has undergone several tampering, redirects in the coeval Amalfi and cloisters of San Domenico in Salerno and Santa Sofia in Benevento, in scores quadrifore with horseshoe arches, testifying to Muslim influences. Adjacent to the cloister is the great Hall of the Chapter, in the 13th century, in which they placed some fine Roman sarcophagi, attributed mostly to the third century a.d. Very evocative are also environments, different era – made from the 9th-10th century with later renovations in XII-underground in the badia and the cloister, the so-called "Lombard cemetery", used for the monks ' cemetery and trees that , for devotion, wanted to be buried.