There is yet another old road which was lately discovered.  It is about three hundred yards below the city and near the road that cuts through from Porta del Sole to the church of Madonna dell’Aquila.[77] This road is made of polygonal stones of the limestone of the mountain, and hence is older than any of the lava roads.  It runs nearly parallel with the Via degli Arconi, and takes a direction which would strike the Via Praenestina where it crosses the Via Praenestina Nuova which runs past Zagarolo.  That is, the most ancient piece of road we have leads up to the southeast corner of the town, but the oldest tombs point to a road the direction of which was toward the southwest corner.  However, all the roads lead toward the southeast corner, where the old grade began that went up above the arches, mentioned above, to a middle gate of the city.

The gate S. Francesco also is proved to be ancient because of the old road that led from it.  This road is identified by a deposit of ex voto terracottas which were found at the edge of the road in a hole hollowed out in the rocks.[78]

The two roads which were traveled the most were the ones that led toward Rome.  This is shown by the tombs on both sides of them,[79] and by the discovery of a deposit of a great quantity of ex voto terracottas in the angle between the two.[80]

THE WATER SUPPLY OF PRAENESTE.

In very early times there was a spring near the top of Monte Glicestro.  This is shown by a glance back at plate III, which indicates the depression or cut in the hill, which from its shape and depth is clearly not altogether natural and attributable to the effects of rain, but is certainly the effect of a spring, the further and positive proof of the existence of which is shown by the unnecessarily low dip made by the wall of the citadel purposely to inclose the head of this depression.  There are besides no water reservoirs inside the wall of the arx.  This supply of water, however, failed, and it must have failed rather early in the city’s history, perhaps at about the time the lower part of the city was walled in, for the great reservoir on the Corso terrace seems to be contemporary with this second wall.

But at all times Praeneste was dependent upon reservoirs for a sure and lasting supply of water.  The mountain and the town were famous because of the number of water reservoirs there.[81] A great many of these reservoirs were dependent upon catchings from the rain,[82] but before a war, or when the rainfall was scant, they were filled undoubtedly from springs outside the city.  In later times they were connected with the aqueducts which came to the city from beyond Capranica.

It is easy to account now for the number of gates on the east side of the city.  True, this side of the wall lay away from the Campagna, and egress from gates on this side could not be seen by an enemy unless he moved clear across the front of the city.[83] But the real reason for the presence of so many gates is that the best and most copious springs were on this side of the city, as well as the course of the little headstream of the Trerus.  The best concealed egress was from the Porta Cesareo, from which a road led round back of the mountain to a fine spring, which was high enough above the valley to be quite safe.