The historic landscape of the present-day municipality of Fossa is the result of a series of changes in settlement form over a long period of time, during which the Iron Age and pre-Roman (village and defences of Monte Cerro, the cemeteries of Aveia), Roman (praefectura of Aveia) and medieval settlements were distributed within an area of a few square kilometres without any destructive superimposition. With the aim of documenting the Roman evidence (walls and probable remains of a theatre) and considering the fact that the Roman town of Aveia, identified in the 18th century, had never been the object of systematic research, the “Orientale” University of Naples in agreement with the Archaeological Superintendency of Abruzzo, programmed for 2007 a series of georadar surveys and trial trenches. The earthquake of the 6th April 2009 caused of tragic destruction to the urban fabric of the modern town of Fossa. This made an intervention to identify and recover the archaeological evidence within the territory even more pressing, not only in order to save what was preserved of ancient Aveia, but also for the sensitivity and interest shown by the local populations towards their origins following the excavation of the great necropoleis. It was seen that archaeology can represent a cohesive factor for a community whose historical and cultural identity had already been put to the test by the population decline caused by the great migrations in the second half of the 20th century. The interest of the team from the “Orientale” was concentrated on studying the walls of Aveia, with the aim of helping to protect the site by clearly identifying its extension, in particular the “low” part of the town where the walls had disappeared from sight, and of defining the entity and chronology of the ancient interventions, from the foundation of the Roman settlement to that of its abandonment. The first intervention was the identification and cleaning of all the parts of the walls that could be seen, most of which hidden by thick vegetation, in order to undertake a detailed 3D survey. In the “low” part of the town, in particular the area thought to coincide with the south-eastern corner of the town walls, two trenches were dug and a stretch of wall circa 120 m long was cleaned. What emerged from the excavations demonstrated that at this point the walls, which were slightly curved as prescribed by late Republican treatises on architecture (Vitruvius, I, 5, 5), clearly bent to form a corner between the east and south stretches. In order to provide better protection for this sector, obviously considered very vulnerable, a semi-tower was built abutting the walls. The preliminary interpretation (prior to further excavation) is that this was either a space housing war machines (catapults or ballistas), shelter for the guards or a tower flanking one of the town gates. The systematic robbing of the walls, which continued for a long period after the abandonment of Aveia, renders dating of their construction difficult. Despite this, on the basis of finds recovered in the foundation trench of a channel built at the same time as the walls, it is possible to suggest, for the moment, that the town walls date to the first decades of the 1st century B.C.

In 2010 as part of the programme for the study and protection of the archaeological remains of ancient _Aveia_, a laser scan was made of the south-western section of the curtain wall protecting the “high” part of the town and built along the steep slopes of Monte Circolo. This stretch of the fortifications, built in opus caementicium, preserved for a length of circa 250 m and standing to an average height of 3 m, had not been previously recorded in detail, despite the fact that the facing, built in a sort of “small polygonal masonry”, has survived almost intact. A small trench, dug at the point where the wall bent to form an obtuse angle, demonstrated that this anomalous alignment had been conditioned by a notable change in the level between the “lower” and “upper” parts of _Aveia_ (from 575 to 600 m a.s.l.), which in fact isolated the summit, probably constituting the _arx_. The clearing back of the dense vegetation which had formed over the last thirty years revealed, behind a stretch of the Roman fortification completely robbed in the medieval period, the remains of an earlier substructure in polygonal walling. On the basis of the construction technique and the stratigraphic relationship with the cement fortification, this structure can be dated to the pre-Roman period, although at present it is not possible to be any more precise regarding construction date and function.

The excavation of the southern section of the walls of _Aveia_, undertaken in July 2011, confirmed that, in antiquity, the meeting point between the stretch delimiting the “upper city” and that coming from the “lower city” made use of a substantial natural difference in height. In fact, the foundation of the sector coming from the “lower city” was reached at 2.30 m below present ground level, which was artificially created by modern agricultural terracing. The same agricultural operation also completely uncovered the deep foundations (average height 2.50 m) of the wall surrounding the “upper city”, presumably the site of the _arx_ of _Aveia_. In the post-antique period, one or more landslides buried most of the stretch of wall coming from the “lower city”, guaranteeing its preservation prior to the systematic robbing to which all this part of the walls was subjected. Unlike the walls of the “upper city”, made of small polygonal blocks, the facing of this sector – perfectly preserved in the excavated part – was built in uniform _opus reticulatum_. This indicates that diverse building sites were working at the same time and operated in complete autonomy, choosing from among the revetments in fashion at the time those deemed most suitable to the building’s function: the decorative type on the stretch in the “lower city”, more structural than that used to enclose and support the _arx_. Lastly, the excavation uncovered a lime-kiln, created to deal with the stone robbed from the corner formed by the meeting of the two sections of wall. Thanks to the excavations undertaken between 2009-2011, the walls of Aveia have been inserted into the plan for the recovery of Fossa’s monuments: the town at present is still abandoned due to the damage caused by the earthquake of the 6th April 2009.

The 2012 campaign investigated a sector of the ancient town of Aveia (Fossa, Aq). The aim was to check both the chronology and function of an ancient building, reused up until the modern period and known locally as the Palazzo del Re. The structure, constituted by two flanking rectangular rooms, was damaged by the 2009 earthquake. Characterized by the presence of numerous ancient structures, of which only the nucleus remains, It was reused for creating the present rooms. In particular, the southern perimeter wall that delimits the two rooms, the eastern perimeter wall of the residential room and the dividing wall between the two rooms can certainly be dated to the Roman period. This season concentrated on the cleaning of two rooms, above all clearing away the thick vegetation both inside and outside of the building. The eastern side of room A, where an entrance was present, was emptied and a trench was put into the southern part. In the southern part of room B, a trench was opened along the eastern perimeter wall in order to check the sequence of the walls, as seen in the vertical stratigraphy. In order to check the state of preservation of an _opus reticulatum_ wall identified by M. Alimonti in the 1970s, a second trench was excavated north of Palazzo del Re, in the area of the so-called Aia dell’Osteria, at just over 50 m from the Palazzo. Abutting a containing wall in reinforced concrete were a Roman wall without facing and a completely buried vaulted room.