The roads are the present Via Prænestina toward Gallicano, and the Via Prænestina Nuova which crosses the Casilina to join the Labicana. This great deposit of terra cottas was found in 1877 at a depth of twelve feet below the present ground level. Fernique, Revue Arch., XXXV (1878), p. 240, notes 1, 2, and 3, comes to the best conclusions on this find. It was a factory or kiln for the terra cottas, and there was a store in connection at or near the junction of the roads. Other stores of deposits of the same kinds of objects have been found (see Fernique, l.c.) at Falterona, Gabii, Capua, Vicarello; also at the temple of Diana Nemorensis (Bull. dell'Inst., 1871, p. 71), and outside Porta S. Lorenzo at Rome (Bull. Com., 1876, p. 225), and near Civita Castellana (Bull. dell'Inst., 1880, p. 108).
Strabo V, 3, 11 (C. 239); ... διωρυξι κρυπταις--πανταχοτεν μεχρι των πεδιων ταις μεν υδρειας χαριν κτλ. ; Vell. Paterc. II, 27, 4.
As one goes out the Porta S. Francesco and across the depression by the road which winds round to the citadel, he finds both above and below the road several reservoirs hollowed out in the rock of the mountain, which were filled by the rain water which fell above them and ran into them.