Entering the Cathedral of Saints Peter and Paul in Adria and walking down the central nave, on the third pillar on the left at a height of three metres, one may note a quadrangular stone icon (ca. 54x52 cm), set in a 19th-century marble cartouche which describes it as the oldest work of Marian devotion in the Veneto, datable to the fourth century, and coming from Ephesus. However, these facts have no historical basis, since no source is able to clarify its exact date and origin.

The two archangels, on the left Michael and on the right Gabriele, are almost identical: they stand upright, holding their right hand raised as a sign of greeting while in the left they hold a globe surmounted by a cross. Mary, seated on a stool, holds both her hands raised as if in prayer, while the Child on her knee seems to be blessing with his right hand and holding a globe or parchment with his left; but continual touching by the faithful, or perhaps rainwater, has in the course of time worn down the relief. It is theiconography of Mary that makes this work almost unique of its kind, in that it embodies both the model of the Virgin Queen, that is, of the Madonna seated on a throne intent in holding the child in her lap with her hands, and that of the Virgin in Prayer, where Mary is standing apart with her palms raised as a sign of prayer. It seems, in fact, that there is only one other comparable piece: a miniature from the 6th-century Coptic Evangeliary of Egmiadzin. Therefore, it is assumed that this Marian icon is a contemporary that one and comes from Egypt, perhaps thanks to the mediation of Ravenna or Venice.