CHAPTER 5: The Horreum or Barn at Site 10
See "Site 10: Horreum or Barn - Plans and Reconstructions" section of this report for room designations by number.
Perhaps the most intriguing discovery at Site 10 was a huge structure (79 meters in length and 19 meters across) part of which functioned as a horreum for grain storage and part as a barn, the latter likely providing stalls for livestock as well as more storage for agricultural produce. 57 A second storey is postulated for the grain storage end of the building, that on the north, which then would have accommodated living quarters reached by exterior staircases. In view of this multiple function might the building qualify as a villa rustica?
This Horreum/Barn was constructed within the boundaries of the Site 10 Villa's western garden but it did not incorporate the preexisting walls of the garden as foundations. This unusual location presumes the prior leveling of the Imperial Age Site 10 Villa and the need for maintaining access to the underground chambers along the western slope of the site.
If location raises questions, so does the dating of this new structure. Its exterior masonry is composed of rubble concrete foundations supporting a concrete core faced by small rectilinear tufa blocks set in even rows and interspersed by occasional brick (tile) bonding courses. This is a masonry type (opus vittatum) which in the area of Rome can be dated anywhere from the late 3rd through the 6th century A.C., possibly even later. Its masonry alone, withholding other considerations, makes plausible a late 4th or early 5th century A.C. date for the construction of this Horreum/Barn.
Pottery gives little further dating information, but Carbon 14 dates of some thirty three burials surrounding the Horreum/Barn at its northern end and pushed up against its walls are indeed useful in filling the gap (see the “Human Skeletons” section of this report). Here we have a range from the 3rd to the 13th century, give or take one hundred fifty years, confirming a possible late 4th or early 5th century time of construction and then a life span through at least the late 9th century A.C.
The extremely large size of the Horreum/Barn seems excessive if the estate retained its maximum twenty hectare size. We know that the late 4th century-early 5th was a time of turbulence throughout the Mediterranean world and pirates had destroyed many of the sea routes for the shipment of grain to the citizenry of Rome. The shift from wine and olive oil production to grain for Rome's outlying farms and villas was a necessary consequence; so too, the consolidation of its suburban estates under a single authority, most likely that of the Papacy. 58
The design of the Horreum/Barn, even if unique for its time, is surprisingly straightforward. At its northern end are three chambers (rooms 1,2, and 4), two flanking a corridor (Room 3) and one on the far north of the building cutting across its full width. This last chamber (Room 4) was both concrete vaulted and had a concrete floor raised above a ventilation space cut from the bedrock. Great slabs of concrete, some with a curved profile, provide the evidence for ceiling and floor and also give proof that the function of this sealed chamber was the storage of threshed grain. The two chambers or rooms flanking the corridor each have a large central pier. These piers could easily have supported a floor for a second storey. The accumulation of rubble and debris found at this northern section of the site before and during excavation strongly suggests a two storey elevation. Since there was no extant masonry staircase emplacement within the building, I propose outside wooden stairs. This would conform to the design of several barns with second storey residential quarters at one end found today in the immediate area of Gabii.
The northern grain storage rooms of the Site 10 Horreum/Barn just described are raised by two steps (Room 5) above a long tile paved central space (Room 9) of an attached barn-like unit. This central space is enveloped by aisles (rooms 6,7, and 8) somewhat less in width which seem to have been unpaved. Large piers resting on a stone plinth separate the central space from its surrounding aisles and would have carried the wooden roof beams of this southern unit.59 A wide side entrance on the east just below the northern stepped platform, and another entrance midway in the southern perimeter wall would have given access, even to farm carts, to the interior of the building. As said earlier, this southern unit of the Horreum/Barn could have provided more storage facilities for agricultural produce and perhaps also stalls for livestock.60
There is no doubt that this Horreum/Barn of Site 10 attests to a new architectural form in antiquity, hitherto unknown, but also to extreme changes in the economic and social patterns of suburban Rome in the 3rd to 5th century A.C. Until now these shifts have been put forward by archaeologists and historians but without the proof of excavation. Also Site 10 highlights how little the remains and artifacts of the countryside in Italy have been investigated by true scientific means.61