The Crypt of Original Sin was the cultic place of a Benedictine rock coenoby of the Lombard period. It is embellished by a cycle of frescoes dating back to between the 8th and 9th centuries, painted by the artist known as the Flower Painter of Matera and expressing the historical characteristics of Benedictine-Benevento art. The left wall is enlivened by three niches, on which are depicted respectively the triarchies of the Apostles, the Virgin Queen and the Archangels. The back wall, instead, is enlivened by a large pictorial cycle depicting episodes of Creation and Original Sin.