Dug at the base of a rocky wall belonging to the Ruccia pit, it is the cave to which the masonry church was added, probably during the Middle Ages. Due to an earthquake in 1693, the boundary wall collapsed, leaving the opening of the cave free. It was later closed with the gate which is still there today.
Above the gate, in the window, a small church bell was placed.
Next to the ecclesiastical compartment there is another example of a cave environment. It does not communicate with the first cave and has no relevant feature; it was probably used as a residence and later as a sacristy.