Carved into the rock of the tufa plateau –a sedimentary area that is a result of volcanic activity — on which the city stands, the subterranean structures were largely filled. Only the top-most modern layer was visible.
“Within this upper section, which had been modified in modern times and was used as a wine cellar, we noticed a series of ancient stairs carved into the wall. They were clearly of Etruscan construction,” David B. George of the Department of Classics at Saint Anselm, told Discovery News.
As they started digging, George and co-director of the excavation Claudio Bizzarri of the Parco Archeologico Ambientale dell’Orvietano noted that the cave’s walls were tapered up in a pyramidal fashion. Intriguingly, a series of tunnels, again of Etruscan construction, ran underneath the wine cellar hinting to the possibility of deeper undiscovered structures below.