A great tank opens in the basement of Piazza Matteotti: completely renovated and made accessible, its perfectly preserved environments demonstrate the growth of urban America, which became municipality in 90BC, at the time of Romanization. At the end of the first century it was estimated by Strabo as one of the most Romanized cities worthy of mention ih the Augustan Umbria. This first phase of ‘Romanization’ had to date at the beginning of the urban planning process, which is still possible to reconstruct in broad characters, albeit buried and hidden from the massive overlapping medieval and modern buildings.
In the northern side of the city, on a flat area extending between the two heights currently occupied by the hospital and the Cathedral, built right on the site of the ancient arx, was the Forum square, the urban hub of the Roman city (now Piazza Matteotti): of the ancient paving, two slabs survive, reused on the steps of a staircase on the corner of Via degli Archi and Via Geraldini. On one of these steps you can still see a groove shaped like the letter V: the recess was once filled with bronze, a technique that allowed the most prestigious inscriptions to be noticed, read and remembered by the dozens of people who frequented the Forum daily.
At the same chronological period the city had to be provided with the necessary water supply structures: a large underground cistern was dug in the limestone massif and served as a substructure for the forensic audience. This impressive property is still perfectly preserved and extends in the basement below the square, until the beginning of Via Garibaldi. It is rectangular (internal dimensions: 57.50m x 19.60m; average height 5.70m), divided into ten parallel environments with vaulted ceilings and communicating with each other via vaulted passages as well. The walls and partitions were lined with masonry cement of uncertain origin, the vaults in conglomerate. Environments 1 and 10 of the outer walls are covered with a plaster of “cocciopisto” often 6 cm thick. Cylindrical wells on the top were used to draw water and to ensure air circulation.
In environment 10 “fistule aquariae” were identified, relevant to the supply pipe and a stem with a rectangular opening for draining water. From an open pit between the last environment and the mouth of the tunnel, a bulkhead was operated that regulated the water discharge. The water was finally guided along the tunnel exhaust, covered by an indoor Capuchin, running East, underground, along the axis between via Garibaldi and via Posterola, going beyond the walls and outside Posterola gate.
The construction of the tank is placed between the start and the middle of the 1st century B.C. Between the late first and early second century A.D. a construction equipped the South East corner of environment 1 with a platform jacket with brick bipedales. With the name engraved in stamps found on these bricks, the workshop and the successive restoration could be traced, directed by Caius Atilius Fortunatus.