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The Aniene valley and Villa Gregoriana in Tivoli

Date of Submission: 01/06/2006
Criteria: (i)(ii)(iii)(iv)
Category: Cultural
Submitted by:
Ministry of Cultural Heritage and Activities
State, Province or Region:

Region: Lazio - Province: Roma

Ref.: 5008

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The Tiburtino territory, characterized by a richness of its waters and a particular geomorphological conformation of the valley crossed by the Aniene River, was frequented already in very ancient times, as shown by the numerous remains of the first civilization that settled there during the Upper Paleolithic. In the caves near Ponte Lucano, along the travertine embankments on the right bank of the river, were found flint tools, deer bone fragments, and numerous objects decorated with geometric and animal figures made from river pebbles.

The Aniene River is the territory's most important stream; it originates at the boundary between the Latium and Abruzzo regions, in the Simbruini Mountains, unwinds through the valley to reach Tivoli and, after the drop in height over the large waterfall, arrives, through the Roman campagna (countryside), to Rome, where it flows into the Tiber. The abundance and continuity of the waters feeding it make the Aniene a river of a good capacity, used since ancient times to supply aqueducts. The river has always been an important economic resource for the town of Tivoli: navigable from Ponte Lucano, it was the main route for transporting travertine to Rome. In the Tivoli area, the production activities that settled in the territory, first handicrafts and then industry, exploited the energy supplied by the water for motive power. With the power supplied by the Aniene water drop, the first hydroelectric power plant was built at Acquoria and opened in 1886, making the town of Tivoli the first one in Italy to have electric lighting.

Collection of the waters of the Aniene began in the mid-2nd century BC with the first aqueduct built by the praetor Quintus Marcius, to which two more were added during the age of the Claudii, along the same axis and overlapping or parallel in some points. Thence the name "Acqua Marcia" given to all of these waters which provided, and still contribute to, Rome's water supply.

The bond between the Aniene and the town of Tivoli is ancient and deeply rooted. The very short stretch of the river lying between the San Giovanni basin and the Citadel had an influence on the life and the primitive arrangement itself of the town of Tivoli. The water drop of the "great waterfall", which forced the riverbed to make an abrupt turn, and the geomorphological and geological conformation itself, with soft limestone sedimentation, were conducive to the cutting of a deep riverbed with caverns and sacs of an instable nature. Since the slope on which the town's original nucleus stood was at a level slightly lower than that of the river, considered near the present-day Ponte Gregoriano, it became possible to create canals to serve the homes and for the creation of the extraordinary garden of Villa d'Este with its fountains and plays of water. The main framework of this network of canals dates back to ancient times and aided the establishment of production activities along the ridge, from the Citadel to the Sanctuary of Hercules.

The marked natural characteristics, together with the dangerousness of the river system and the presence of an obligatory crossing point for traffic between the Roman land and the Sannite populations, made the waterfall area, from the origins of its history, a strategic point and sacred place of reference. The two famous temples of the Acropolis, the Temple of Tiburnus (or of Vesta) and Temple of the Sibyl (3rd-2nd c. BC), are the most direct evidence, but a third, which no longer exists today, allegedly stood on the opposite riverbank, where a terracotta pediment with figures identifiable as characters from the myth of the Argonauts was found in 1835. In the same area, on the basis of ancient literary texts, allegedly stood both the temple of the Sibyl Albunea, a goddess connected with water, and the Tiburni lucus, a grove consecrated to the eponymous founder of Tibur, where the very widespread cult of the sacred oak was probably practised. Somewhat more toward the valley stood the largest sanctuary on Italic soil dedicated to Hercules Victor, protector of shepherding and trade, also considered a reclaimer of uncultivated and marshy regions, knower of caverns, creator of canals, dams, underground galleries, regulator of rivers, and protector of the land, thus the best god to protect a town that was frequently threatened by the river's flooding and vehemence.

Indeed, since antiquity the river, which formed a wide bend around the Acropolis, then falling from the hard limestone base toward the plain, periodically gave rise to disastrous floods that continued to carve out its bed: Pliny the Younger described a ruinous one that destroyed houses, villas, and monuments in the year 105; others are described by local news reports in 1688 and 1689, and, lastly, in 1826.

The Villa Gregoriana was created out of the necessity to defend the town of Tivoli from the ruinous floods of the Aniene. The villa is positioned in a very steep valley, in ancient times called the "Valley of Hell", carved out at the foot at the ancient acropolis of Tivoli by the river which here, in two drops, descends over 130 metres. The site was strategically important in the communications between the shepherding peoples of the Aniene Valley and the Tiber Plain from the archaic age. It was here that, upstream of the great waterfall and subject to the supervision (and tolls) of the Tiburtine Acropolis, the first bridge had been built. This position was one of the strategic reasons for the birth of the ancient Tibur, and the rocky spur on which the acropolis and the ancient residential area arose because it was geologically and hydrologically very difficult, was "cultivated" at least from the 2nd century AD. In fact, also thanks to the calcareous and karstic nature of the terrain, there are at least 12 known manmade hydraulic structures - ditches, canals, locks, and branches of aqueducts - without counting the remains of bridges and mills, used to divert, control, and use the variable pressure of the waters, many of which are still in use or, in any case, accessible.

The fame of the place, dating back to antiquity, is seen in numerous literary references, including verses in Horace's "Odes" and the passage from Statius's Silvae, which describe the villa of the Roman patrician Manlius Vopiscus, the remains of which are at the site.

Numerous pictorial representations of the crag of the Acropolis, with its temples and the drop of the Aniene, bear witness to the good fortune enjoyed by the place, which never ended and reached its peak between the 18th and 19th centuries: the first work done to render the place accessible to the travellers of the Grand Tour was carried out during the Napoleonic period, in 1809, as ordered by the Governor of Rome. The nature of the places was modelled according to the neoclassical taste, with the creation of avenues and belvedere stopping points and, to permit visiting the Cave of Neptune, a tunnel was dug into the rock, with side openings offering impressive views of the underlying chasms (Miollis tunnel). The ruins of the Roman Age buildings, grown wild down through the centuries, were carefully restored and integrated into the garden, where new plants were planted and paths, walkways, stairways, and utility and service rooms were laid out.

The disaster caused to the residential quarter by the flood of 1826, which had destroyed almost all the homes situated in the oldest part of the town, moved the government of the Papal State to intervene. Worldwide resonance was given to the drafting of the plans, and numerous foreign architects took part in the competition. Almost all the plans proposed the construction of high walls and embankments, diverting any floodwaters into effluents. The winning proposal was that of Clemente Folchi, who suggested diverting the bed of the Aniene. In 1832, a huge and spectacular project thus began to divert the river by means of the so-called Cunicoli Gregoriani (Gregorian Tunnels), two 300-metre tunnels of a width varying from 10 metres at the entrance to 7.20 at the exit, dug under Mount Catillo, so as to move the course of the Aniene and the falling point of the water further away from the residential area.

The project was authorized and financed by Pope Gregory XVI who, on 7 October 1835, watched the spectacle of the first prodigious drop of the water in the new great waterfall. The work was not limited to just the rerouting of the river, but also included the construction of two vast squares, Piazza Rivarola and Piazza Massimo, joined by the bridge called Ponte Gregoriano.

The Villa Gregoriana is actually an "accessory" of the primary structure, which is the hydraulic structure. Set over the ancient Roman villa of Manlius Vopiscus, the Villa was built in 1834 on the basis of the directives of Cardinal Rivarola and carried out under the control of Msgr. Massimo and the architect Folchi. The park of the Villa, which stands in the chasm of the former course of the Aniene, to the left of the great waterfall (in the so-called baratri tiburtini - Tiburtine chasms), is an admirable synthesis of the natural landscape with the well camouflaged manmade one overlapping it. Situated immediately below the ancient Acropolis of Tivoli, the Villa is dominated by the Roman temples attributed to Vesta, the Sibyl, and Tiburnus which, although they are just outside its boundaries, can rightfully be counted as part of the considerable archaeological heritage of the site. The old riverbed and the steep walls delimiting it were used to create a walkway amidst limestone formations, caves, gorges, and archaeological remains, still of impressive beauty today. A spectacular view is that of the drop of the Great Waterfall, magnificent and impressive in the powerful rush and roar of its water. Descending further, we find the dark green of holm oak, cypress, and pine trees; then the water that falls in front of the Cave of Neptune and forms a pond, then sinking into the Cave of the Sirens.

Today, the current arrangement of the site, the ownership of which was transferred in 1870 from the Papal State to the Italian Government, even if this was determined by the need to regulate the waters of the Aniene, is - with its archaeological structures, remains of various ages, and exceptional natural elements, caves and panoramic views - a place of enormous environmental, historic, and artistic value.

The complex is a fundamental element in the uninterrupted history of the territory of the Aniene Valley, which well represents, in our eclectic culture - together with the monumental complexes of Hadrian's Villa and Villa d'Este - the relationship between Man and Nature from antiquity to the present day, and bears witness to a path, not only ideal, through the various historical periods. In fact, these structures are significant examples of the different ways in which Man has related to Nature, creating an interaction between architecture and nature throughout history: from the philhellenism of the age of Hadrian, expressed in the conception of Hadrian's Villa, to the mannerist order of the Italian style garden, of which Villa d'Este is an extraordinary example, to the sentiment of the Sublime in Nature expressed in the park of Villa Gregoriana, with a uniqueness already recognized by the travellers of the Grand Tour.

Statements of authenticity and/or integrity

Today, the places of the Villa Gregoriana site, with the Acropolis and temples, the ruins of the Villa of Manlius Vopiscus, and its landscape heritage are in a good state of preservation. After the recent restoration and reopening of the site to the public, it maintains the identity and authenticity of the ages that characterized it, from the hydraulic routes and structures already present in the classical age (such as the Stipa or the Pelago canal) to the hydraulic works of the Gregorian plan (bridge and tunnels of Gregory XVI).

Even the archaeological finds along the ancient routes, which connected the underlying plain of the valley from the Acropolis to the present-day Castel Madama branch road, bear witness to the persistence of the frequentation of the site with the archaeological ruins and the traditional landscape of the campagna romana, which is still practically intact.

The integrity of the Villa Gregoriana and the other individual monuments as well as of the surrounding landscape is guaranteed by the protective measures in force, which are based on the national legislation safeguarding cultural heritage and landscape (Legislative Decree 22 January 2004, n° 42 "Cultural Heritage and Landscape Code").

Comparison with other similar properties

To find possible comparisons with similar work on the environment, which can constitute prominent examples of landscape design, it is necessary to refer to the dominant culture of the late 18th and 19th century of the literary and artistic world, in particular in England and central Europe, with regard to changes made to the natural environment in parks and gardens respectful of the preservation of the identity and authenticity of the sites.

In particular, at Villa Gregoriana, the work of the Napoleonic period on the significant example of the romantic path of the General Miollis tunnel refers to French and English models in the designs of characteristic gardens and parks of that period, which were certainly innovative compared to the designs normally used in Italy during that time.

As for the natural frequentation of the communities settled along the beds of the main rivers down through the centuries, a comparison can be made with prominent examples both in Rome and in other European capitals, shown by the historic iconography with architectural and landscape structures incorporating elements of classical archaeology, industrial archaeology, and the historic path systems present at the sites.