The Rediscovery

by Prof. Lorenzo Quilici, University of Bologna
translated by Ted O'Neill


The Aqua Traiana was the penultimate of the eleven great aqueducts which supplied ancient Rome. It was inaugurated on June 24th, 109 A.D. to supply the urban zone of Trastevere and the city at large. It remained continuously functional, save a few interruptions, up to the period of the barbarian sieges in the sixth century AD, when Goths and Lombards seized and cut it. In the early 1600s, Pope Paul V undertook the restoration of the Traiana in order to guarantee the abundant provision of clean fresh water both to the Vatican and Trastevere. The “Fontanone” Display Fountain on the Janiculum Hill stands at the end of the aqueduct, which became known as the Acqua Paola.


Drawn from springs around Bracciano's volcanic basin, the Aqua Traiana was initially a pure and fresh water supply. But later in the seventeenth century it was plagued with problems of hygiene and purity when it took the water from Lake Bracciano at Anguillara in order to increase the supply. On the other hand, the original Roman aqueduct relied completely on fresh aquifers and captured all its water from clean springs along its route. The hills around the northern and eastern banks of the basin are rich with water: from Manziana to the Baths of Vicarello, to Trevignano and Anguillara where the channel proper begins. The water channel enters Rome at the ancient Aurelian Gate, today’s St. Pancras’ Gate.


The Roman aqueduct had the additional feature in Trastevere of the rapid drop in height offered by the Janiculum Hill. This was exploited to supply motor force to a chain of flour mills built in rows along its slopes: a real pre-industrial top-of-the-range facilty. The motive force was exploited again in the late sixteenth century when a new series of mills were constructed along what is now Via Garibaldi.


The Emperor Trajan minted coins to celebrate this work, which was constructed at his own expense. The sestertius coin shows a reclining figure of a river god under a great arch flanked by columns. This has previously been interpreted as the image of the ‘Display’ of water that Trajan must have built on the Janiculum, 1500 years before the great fountain of Pope Paul V.


The headwaters of the Roman aqueduct, constituting the first spring along the route around the lake, and the most important, remained forgotten in recent centuries until its re-discovery came about in extraordinary and adventurous circumstances.


Two British Citizens, Mike and Ted O’Neill, were preparing a series of documentaries regarding the ancient Roman Aqueducts for MEON HDTV Productions Ltd, researching the Trajanic conduit along the lake, when the Architect Giuseppe Curatolo, student of the Bracciano’s Odescalchi Aqueduct, directed their attention towards the springs which supply the local people of that city.


In a rough and wild patch alongside a stream, there is a spacious grotto that contained a chapel of the Virgin Mary. Today it’s an abandoned ruin, and at the bottom of the cavity, in her honour, there remains a beautiful molded baroque picture frame that would have contained her image. The cave is artificial and on each side of its great vault extend ancient crossed-vaulted rooms. These contained the springs. The rooms may have been reconfigured by the Odescalchi princes at the start of the 1600s when the the course of the waters was diverted to supply Bracciano, where they still arrive today. The water is currently collected by pumps in two adjacent bore-holes, which supply a good 50,000 cubic metres of water per day, an immense quantity.


Trajan’s Aqueduct, the ancient use of the springs, and the Christian chapel overhead were forgotten when the water was diverted to Bracciano. The ancient monument, however, would have taken the shape of a stunning nymphaeum, constructed at the primary source of the aqueduct: a central chapel dedicated to its god or nymphs, those on each side widened into two basins covered by extraordinary vaults still flecked with Egyptian blue paint. At the base of the side chambers can be seen an ingenious filtering system consisting of blocks laid with gaps between them. Water seeped in two basins, from which the aqueduct channel begins.


The structures are 8-9 metres high and perhaps more, given that they are partially buried and choked with vegetation that covers the site. They are built in very refined opus latericium brickwork and in opus reticulatum, a crosshatched pattern of stone facing for the underlying concrete. The chambers, with barrel and cross-vaults, the wells, the water-collection tunnels that converge there, the channel where the underground aqueduct gallery begins are all today, due to a lack of water, accessible by foot. Realistically, descending into the tunnels is not easy, because the place is overgrown, covered by a dense thicket of gigantic figs that threatens the concrete structures with roots that descend to the deepest level of the nymphaeum.


We can compare this partially subterranean nymphaeum with the Canopus of Hadrian’s Villa or with the Nymphaeum of Egeria in the Triopus of Herodes Atticus on the Appian Way!


The two Englishmen, excited about the discovery and wanting not only to document it but, with a true sense of community spirit, to achieve the stabilization and restoration, excavation and evaluation of this monument, are attempting to involve in the initiative the local authorities, the Superintendents, Italian research organisations and foreign scholars.


It’s their inspired idea that Trajan’s famous coin does not represent his fountain on the Janiculum Hill, but the front of this nymphaeum-grotto, with the reclining god of the spring waters.
The research, restoration and stabilization of such an extraordinary monument requires funds, lots of funds: it is not, however, necessary to do everything immediately, but sufficient to start the work with the conscience and good will to prepare stage by stage the conditions for the future.


Lorenzo Quilici
Università degli Studi di Bologna