In the 11th century the cubiculum was enlarged southwards by digging further into the rodk. It has a southern entry, enlarged in the 13th century, which leads into a tiny vestibule opening onto a shrine with three naves.
The central nave comprises a single bay marked out by four small columns : one is authentic and bears a mask portraying an abbot ; two others are restored, one being cabled and the other showing Moses and the bronze serpent ; the fourth is due for restoration at the end of the southern groin.
The eastward extension dating from the late 17th century was created for the altar attributed to the Puget School, showing the "ravishment" of Mary Magdalene.
A opening giving access to the side chapel in the small basilica has been made by breaking through the niche in the side of the vestibule. This third entry, designed to provide direct communication between the two altars and is of modern origin.