Introduction Project Bibliography
Accademia: Hadrian’s Secret Garden
Pilot Project

Marina De Franceschini

Accademia: Hadrian’s Secret Garden

Pilot Project


Fig. 1 - Plastic model of the Accademia Esplanade with its buildings

Our Pilot Project is focused on one of the lesser known buildings of the Villa, the Accademia and its surrounding grounds. This used to be the ‘Secret garden’ of emperor Hadrian, and it is located on the Accademia Esplanade, the highest of the Villa, its true Acropolis (fig. 1). Among its best preserved structures is the so called Temple of Apollo (fig. 2), which was measured and drawn by some of the greatest architects of the Renaissance, such as Francesco di Giorgio Martini, Andrea Palladio and Pirro Ligorio.

Our Project consists of a new survey, with the help of the most advanced tools of information technology, using new instruments and non-destructive methods, which in most cases have never been used before in this site. Once completed, it will hopefully serve as a model and starting point for surveying other buildings in the Villa Adriana.
In 2006, the World Monument Fund included our Accademia Pilot Project in the list of One Hundred Most Endangered Sites (see website:

Fig. 2 - The so called Temple of Apollo, a circular hall of 13,80 mt. of diameter

Fig. 3 - Il fauno in marmo rosso

State of the Art of the Accademia

The Accademia is still in a private property: since the XVII century it belongs to the Bulgarini family, which lives there and most generously gives permission to scholars to study and survey the site. It is one of the lesser known buildings of the Villa, because it is outside of the public property and it is not open to the public.

Very little is known about past excavations: in the XVI century Pirro Ligorio explored the site; later on Francesco Contini and Giovan Battista Piranesi (XVII and XIX centuries) made some excavations when they were drawing their general plans. In 1630 monsignor Bulgarini found the Barberini Candelabra, now in the Vatican Museum. In 1736-37 Cardinal Giuseppe Alessandro Furietti made a very fortunate excavation in the Accademia: within few months, he found the two statues of Centaurs, the Faun of red marble (fig. 3) and the famous Mosaic of the Doves (fig. 4). All these works of art are now in the Capitoline Museum of Rome.

Fig. 4 - The Mosaic of the Doves

The latest excavations we know of were made by the Bulgarini’s in 1825, finding fragments of columns and painted stucco.
Information concerning the Accademia strongly needs to be verified and updated; it is important to have a detailed picture of its actual state of preservation.
It must also be pointed out that the published plans were drawn with traditional manual methods, so sometimes they are not very accurate and should be checked.

Method and operating schedule

Fig. 5 - Laser scanner is the ideal tool for surveying curvilinear structures as this one in the “Mimizia”

Our Pilot Project has a global and multi-disciplinal approach, and makes the most of information technology in a thorough study of the Accademia, with a systematic room-by-room survey.

We used modern instruments which seldom were employed in the Villa: Total Station with Gps, color Laser Scanner (fig. 5), which gives a ‘three-dimensional copy’ of the structures. We used other instruments that can ‘see’ under the ground surface without excavations, such as magnetometer, geo-radar and geo-resistivimeter. We also plan to use aerial reconnaissance, with Remote sensing, aerial pictures and Lidar (airborne Laser Scanner) surveys.

Our archaeological and archaeometric survey collected new information and data about the building techniques and the building materials used in the Accademia and also about pavements, wall revetments and roofing. We started to study and explore the network of subterranean corridors under the Accademia, with its Cryptoporticoes and access paths, for a better understanding of the relationship between the Accademia, the surrounding grounds and the other buildings of the Villa.

In the Villa Adriana there is a different type of decoration according to the hierarchy and function of each building. The most precious materials (such as opus sectile marble pavements) were used only in the buildings where the Emperor lived; secondary quarters for high ranking personnel had much simpler decoration (black and white mosaics). The other quarters for slaves and servants were located mostly underground or inside the substructures (with white mosaic or opus spicatum pavements).
This hierarchy has been found also in the Accademia, confirming that it belonged to the group of imperial buildings.

Fig. 6 - Biondo Flavio’s XV century text: he rediscovered Villa Adriana in 1450
First phase - Collection of previous bibliography and of archive documents, including ancient drawings, engravings and old pictures.

1 - We catalogued and transcribed the most important antiquarian manuscripts and books about Villa Adriana and the Accademia. For example, the book by Biondo Flavio, who rediscovered the Villa (fig. 6) and the Diaries of Pope Pius II Piccolomini who made it famous in the whole world. We inventoried the manuscripts of Pirro Ligorio, the descriptions of Francesco Contini and Giovan Battista Piranesi, and all the most significant publications from the XVIII century to the present time.

2 - We also inventoried and digitalized the most significant ancient and modern plans; we discovered several unpublished drawings and engravings of the Accademia and surrounding grounds. The most ancient plan was drawn by Renaissance architect Francesco di Giorgio Martini in 1463, then we have some XVI century plans and sketches made by Andrea Palladio and Pirro Ligorio. The general plans of Francesco Contini, published in 1668 (fig. 7) and of Giovan Battista Piranesi, published in 1781 by his son Francesco, after his death (fig. 8) are extremely important: they still are the main starting point for every study.

Fig. 7 - Plan of the Accademia by Francesco Contini, 1668

Several plans were drawn in the XVIII century by french architects who were Pensionnaires of the French Academy in Rome, such as Charles-Louis Clérisseau and Pierre-Adrien Paris, or by the danish architect Caspar Frederik Harsdorff.
The plans of the XIX and XX centuries copied many details from the plan by Piranesi. Only Heinz Kähler made a brand new survey in 1950, together with Eric Hansen, who drew a new plan of the so called Belvedere in 1960. The plan of Salza Prina Ricotti published in 1982 mostly reworked data coming from the antiquarian plans.

Fig. 8 - General plan of Villa Adriana by Giovan Battista Piranesi 1781
Other unpublished data come from two very important projects, and were very generously given to me by their authors.
The first is the survey of professor Friedrich Rakob who worked at the Accademia with the german architects Edmund Faller, Dirk Helfgen and Axel Krück. He studied the Temple of Apollo and surrounding rooms between 1991 and 1993. I was given plans, drawings, pictures and diaries, a very important documentation.
The second one is the Atelier Italia project, carried out by american architects Robert Mangurian and Mary-Ann Ray between 1985 and 1994. With the help of students of architecture coming from the most important Universities of the United States, they measured and surveyed the whole Villa Adriana. They gave me their precious documentation on the Accademia: drawings, pictures, plans. Their data are extremely useful and precious for understanding the Accademia end enormously helped my study.
This phase of the project has been almost completed (80%).

The first results of this long archive research have been presented during a Conference held in Bern (Switzerland) in 2008:
De Franceschini M. Piante antiche e tecnologie moderne nell'Accademia della Villa Adriana di Tivoli (Roma) in Atti del Convegno Historic Maps and Imagery for Modern Scientific Applications Berna, 28-30 novembre 2008 - HASB 21, 2009 p. 163-175 ( and conference programme).

Problems concerning data management and storage were discussed in a Congress held in Vienna (Austria) in 2009:
Marina De Franceschini "Accademia Pilot Project in Hadrian's Villa near Tivoli (Rome, Italy): problems in archiving ancient and modern data". Presentazione a Vienna (Austria), 14° Workshop Archäologie und Computer 2009. Museen der Stadt Wien, Vienna, 16-18 novembre 2009. (

Expected results: our future publications on the Accademia for the first time will offer to scholars a complete collection of the most important documents and publications on the site.

Second phase - Survey of visible and standing structures, with Total Station, GPS, Laser Scanner, Photogrammetry.
Our Total Station GPS survey was carried on during several sessions in 2005, 2006 and 2009. Topographical data has been merged and cross-checked with other information coming from Laser scanner measurements: this instrument was used for the first time in the Accademia by architect Umberto Pavanello, who also made the topographical survey.

The topographical survey has been completed, now we are processing the data, with the help of architect Giorgia Andreatta, drawing a new plan of the Accademia and surrounding grounds. We will also draw elevations, sections and walls, a work that has never been done before; there are just few partial drawings of the elevations of the Belvedere, of the Temple of Apollo and the room east of it.
We are preparing 3D reconstructions, which are the best way to show the appearance and the different levels of the buildings. We already produced a 3D reconstruction of the two most complex structures of the Accademia, the Belvedere and the Temple of Apollo, which were drawn by Brigitta Casieri.

Fig. 9 - comparing the plans by Piranesi, Salza Prina Ricotti and Kähler we see the mistake of a double corridor which does not exist.
During our survey we were able to detect and correct several mistakes both in ancient and modern plans. For example, in the plan by Piranesi there is a double corridor near the Temple of Apollo which does not exist. This corridor appears in all the subsequent plans, including the one by Salza Prina Ricotti of 1982, but it is not shown in the plan by Kähler, who made a brand new survey of the site without reworking previous plans: he noticed and corrected the mistake. (fig. 9, red arrows).

Fig. 10 - One of the Towers overlooking the Fosso di Risicoli discovered during our survey

We also discovered some new imposing structures, which were never surveyed and are unknown in previous literature. It is a series of Towers and retaining walls, about 15 meters high (fig. 10), overlooking the cliff of the Fosso di Risicoli; they were linked by a panoramic hanging Terrace, and were connected to a network of Cryptoporticoes and subterranean galleries located underneath the Accademia.
In the antiquarian plans there is just a simplified straight line indicating the retaining walls and a circular room (hypothetically a thermal plant because of its shape), which in the plan by Piranesi it is surrounded by a series of symmetrical rectangular rooms, hypothetically reconstructed. New data coming from our survey and especially from the work of architects Robert Mangurian and Mary Ann Ray (which was indispensable for reconstructing the circular room) showed that the actual situation was completely different.

Expected results: our new complete and updated plan of the Accademia gives a clear picture of its state of preservation, without the integrations or reconstructed rooms that are not visible any more and are drawn in antiquarian plans. The recent Pianta del Centenario (2006) only surveyed the public part of Villa Adriana leaving out the Accademia, since it is located in a private property; our work will therefore complete the documentation of the whole Villa.

Fig. 11 - The Cryptoporticus in the Accademia substructures

Third phase - Survey of the structures that are not visible any more.
In ancient and antiquarian plans of the Accademia - especially those by Contini and Piranesi - there are several rooms and structures that have disappeared and are not visible any more. These plans also show a network of subterranean service tunnels located underneath the Accademia and surrounding grounds. Very little is known about them, since most of the galleries are filled with dirt; information given by ancient descriptions are generic and often contradict each other.

Since it is not possible to make excavations, we decided to use Geophysics. It is important to point out that this technique is non-invasive and non-destructive: it is possible to ‘see’ the buried structures without an excavation, saving on costs and time.

Fig. 12 - Two of the subterranean galleries under the porch of the Accademia, partly filled with dirt that we detected with Geophysics

First, we focused on subterranean tunnels, measuring their visible and accessible parts with Total station and Laser scanner. It was not possible to use the magnetometer because the area is full of iron-scraps and barbed wire; geo-resistivimeter seemed to be the more reliable method.
We surveyed the Cryptoporticus in the Substructures of the Accademia (fig. 11) and some of the galleries linked to it. In 2007 and 2008 we made another survey, and started measuring the subterranean galleries connected to a staircase near the main porch of the Accademia (fig. 12). This work was carried out by archaeologist Anna Maria Marras for her Master Thesis in Geo-technology, with the University of Siena. The instruments were given by the University of Siena (Italy) notably by the Center for GeoTechnologies in San Giovanni Valdarno, thanks to professor Fabio Mantovani and dott.ssa Marta Bottacchi (fig. 13).

Fig. 13 - the Geo-resistivimeter that we used for our geophysical survey of subterranean tunnels

We tested the instrument starting from the visible and accessible part of the gallery, then we adjusted it to detect the sections partly filled with debris; finally we were able to follow the further bearing of that same gallery in its buried parts. We discovered that it was partly matching with what was drawn in the antiquarian plan of Piranesi.

The preliminary results of this survey were presented as a Poster during the XVII International Congress of Classical Archaeology in Rome: Meetings Between Cultures in the Ancient Mediterranean and then published in the Fasti-Online website:
De Franceschini M. - Marras A.M. "Progetto AcCADemia nella Villa Adriana di Tivoli. Le gallerie sotterranee di servizio: confronto e verifica delle piante antiche e moderne mediante indagini geoelettriche" in Fasti Online 2009:

and also in a Congress held in Vienna (Austria)
De Franceschini M. - Marras A.M. "New Discoveries with Geophysics at Hadrian's Villa near Tivoli, Rome (Italy)". Presentazione a Vienna (Austria), European Geosciensces Union - General Assembly 2009. Gi9 - Near surface geophysics for the study and the management of historical resources: past, present and future, Vienna, 23 aprile 2009. (

In 2010 Dottoressa Marina Sapelli Ragni, Soprintendente for the Archaeological Heritage of Latium, kindly invited us to take part to a new exhibition in the Antiquarium of Villa Adriana near the Canopus: “Villa Adriana. Una storia mai finita“ (Villa Adriana - An unfinished story). We published a presentation about our survey in the catalogue. De Franceschini M. - Marras A.M. “La riscoperta dei percorsi sotterranei dell’Accademia mediante indagini geofisiche” in Villa Adriana. Una storia mai finita. Novità e prospettive della ricerca. Catalogo della mostra nell’Antiquarium del Canopo di villa Adriana 1 aprile-1 novembre 2010. Roma 2010 pp. 105-112.

Using Geo-resistivimeter we plan to continue our surveys and to reconstruct the whole network of subterranean galleries under the Accademia, linked to the Cryptoporticus and the other tunnels we already surveyed.

Fig. 14 - One of the subterranean galleries of the Great Trapezium, 5 meters high and wide, used by carts bringing supplies to the Villa.
Photo by Francesco Lerteri
We plan to detect the bearing of two other subterranean tunnels which were connected to one of the Towers overlooking the Fosso di Risicoli: they are marked only in the plan by Contini of 1668 (see above fig. 7) and are completely unknown in previous literature.

The same method will be used to study the long subterranean service galleries that linked the Tower of Roccabruna to the Accademia. They were drawn in ancient plans and described by antiquarian sources (Contini 1668, Piranesi 1781), but they were never surveyed. Just a small section of these tunnels, near the Nymphaeum over the Canopus, was recently explored by Marina De Franceschini and the group of Speleologists of the Association Sotterranei di Roma, led by Marco Placidi and Vittoria Fresi ( They have been working for several years in the Villa for the Soprintendenza, under the supervision of dottoressa Benedetta Adembri.

The Accademia Esplanade includes the southern part of Villa Adriana with the so called Great Trapezium (fig. 14), an extraordinary network of subterranean tunnels 5 meters high and wide, that were used by the carts bringing supplies to the Villa; traffic and noise were concealed underground. The galleries were surveyed by architects Robert Mangurian and Mary-Ann Ray, who generously gave me their pictures and documentation. The most recent and very accurate study was published by Jens Köhler (see Bibliography) with an updated plan and levels.
The connections of these galleries with the rest of the subterranean road system of the Villa still have to be studied; three smaller galleries linked the Great Trapezium to the Accademia, the Mimizia and the Odeon.

We also plan to explore other buried structures, such as the ‘secret gardens’ of the Accademia, its main inner porch and the so-called Zooteca. We would like to find out if these gardens had a water basin at their center. The same goes for the great artificial Esplanades of the Accademia and the Praetorium: nothing is known about their structure and arrangement, and it would be interesting to reconstruct the ancient landscape.

Expected results: reconstruction of the network of subterranean tunnels; identification of water basins in the gardens, of waterworks. Reconstruction of ancient gardens and landscape.

Fourth phase - Remote sensing and Lidar.

Fig. 15 - Roccabruna, east façade

Fig. 16 - Roccabruna, inner circular hall

Fig. 17 - Accademia, the inner porch
To make the most of modern technology, we also plan to do a large scale survey of the area (see plastic model, fig. 1 above) with aerial pictures, infra-red photographs and also Lidar (airborne Laser Scanner). With these techniques we can ‘see’ under the vegetation and identify hidden structures, since the vegetation can be ‘cancelled’ using a special algorithm.
These techniques were never used in a complex site such as Villa Adriana. The Accademia is covered by a layer of dirt ranging between 0,30 and 0,70 meters, therefore the aerial infrared photography should give good results: we hope that it will be possible to see some of the buried structures shown in antiquarian plans. This is particularly important in the case of the ”secret gardens” and their water basins, since nothing is known about them from ancient sources.
Lidar will also be particularly useful to survey and measure the Towers overlooking the Fosso di Risicoli (see above fig. 10), since they are heavily covered by trees and wild plants, and very difficult to reach. Part of the Towers collapsed, and it will be possible to detect the fallen parts that are partly visible at the bottom of the towers.
In other case-studies, Lidar proved to be very effective to detect ancient roads and to ‘see’ the original features of the ancient ground and landscape. For example we can try to find the paved road that bordered the Cento Camerelle and probably was going further on, towards the Accademia.

The area that we surveyed consists of two great artificial esplanades of the Accademia and of the Praetorium, which are 600 and 350 meters long; they have never been excavated or surveyed before. As we said, we do not have any information about their antique appearance and features; legends say that on the Esplanades there were woods where emperor Hadrian used to hunt.
Once more, these are non-desctructive techniques that provide new data without an excavation, like Geophysics; this phase of the project still has to begin.

Expected results: discovery of other structures covered by vegetation; better understanding of the Towers we identified during our survey. Reconstruction of ancient Landscape.

Fifth phase - Data processing, dissemination and publication of results

Fig. 18 - Accademia, nothern entrance to the Temple of Apollo
We collected a great amount of data and we are working to make them available for other scholars. We are preparing a series of books about the Accademia, to disseminate the results of our work, both on paper and on the Web.

There will be a description of the area involved and its buildings, which will be as follows:
  1. the Accademia and Praetorium Esplanades with their containment walls and substructures.
  2. The main buildings of this area: Roccabruna (figs. 15-16), Accademia (fig. 17-18), the so called Mimizia (figg. 19-20) and the Odeon theater (fig. 21).

  3. Fig. 19 - The so called Mimizia, inner room
  4. The subterranean network of roads and tunnels, which started from Roccabruna, passed under the Accademia and finally reached the Great Trapezium.
  5. Nymphaea and waterworks, such as the Nymphaeum of the Praetorium Esplanade (fig. 22) and the Inferi Grotto (figg. 23-24).

Fig. 20 - Odeon thearer, porticus posta scaenam

For each building there will be a section of the publication collecting the most important previous written sources and descriptions, all available information about past excavations and studies, a catalogue of ancient and modern plans, a selection of the most significant etchings, drawings and engravings, both ancient and modern.
These data will be analyzed and cross -checked with new data coming from our survey and the unpublished surveys of other scholars (Rakob, Mangurian-Ray).
Each room will have a detailed catalogue entry, describing building techniques, decoration, state of preservation and so on.
We will publish new updated plans of the buildings, draw elevations and sections and most of all we will make 3D reconstructions, which is the only effective way to show and explain the different levels of the buildings, with their upper floors and subterranean features.

Fig. 21 - Nymphaeum of the Praetorium Esplanade

Fig. 22 - The Valley and the Inferi Grotto

We will draw a diachronic map showing the building phases, and a series of thematic plans with building techniques, pavements, wall revetments, or the finding spot of the beautiful sculptures that were excavated in this area.

Fig. 23 - The Inferi Grotto

All previous and new data will be processed and stored in a GIS data-base, which is the best way to manage such an imposing amount of information. By selecting a single room (on a plan or in a picture), it will be possible to access all related information, so that there will be the widest possible dissemination among scholars, for teaching, preservation and knowledge. With an user-friendly system.

Expected results: the GIS data-base will be a very important and effective tool for the Soprintendenza Archaeologica del Lazio as far as the preservation of the site is concerned, in order to plan restoration and maintenance.
Virtual 3D reconstruction will be based on actual evidence; it will be possible to make ‘virtual visits’ of the Accademia, since it is not open to the public.

©mdf2010 Marina De Franceschini