Located just outside the main village in the "Bagnoregio high" area, this cave was carved into the tuff. It is a mystical spot—an ancient Etruscan tomb where history tells that St. Francis of Assisi miraculously healed the young Giovanni Fidanza, who later became St. Bonaventure.

It serves as the spiritual bridge between the mystical faith of Umbria and the volcanic stone of Lazio.