The little church of S. Maria di Mércuri built, probably, by monks from Syria between the sixth and seventh centuries, is among the most important rock churches of Orsomarso. The architectural characteristics of the building are linked to the numerous churches in byzantine period built in various places in Calabria, in southern Italy, but also in Asia Minor, especially in Cappadocia: a single rectangular nave, a side entrance and a semi-cylindrical apse oriented towards the east. On the side wall where is the entrance, three single-lancet windows are intended to dimly illuminate the area occupied by subsellia. On the wall opposite the entrance, appear traces of frescoes including the representation of a kind of cartouche occuped by latin inscriptions. Inside, a statue of the Madonna represented seated, with a sphere in his right hand and the Child, holding a book, on the left leg, made of mortar and stone and dated within the Lombard period.