Niche carved in the rock under a mountain

In Terracina (Italy), near the Church of the Santissimo Salvatore, on a ridge which was next to an ancient path there is a small almost square niche carved into the rock of 0.38 x 0.37 meters. Above the niche there is a recessed more large in which two figures are carved in relief. Unfortunately it is not possible to define what is represented as the color limestone dark has covered precisely these images for which it would be necessary to remove the same to hope to have some more details. Moreover, as witnessed by the owners of the area where the niche is located, during the second world war this rocky wall has suffered cannonades by part of an allied ship that tried to hit German positions between the rocks. We were told that the cavity of the Catena cave, next to the site, had been used as an ammunition depot as numerous cases were detected.