The rural settlement of Palazzaccio, built on the right bank of the river Auser in the late Republican period, shortly after the foundation of the city of Luca, stands in the northern part of the Sesto floodplain. The layout of the settlement has yet to be defined.

The north-western area is of great importance. Here a production complex came to light comprising a lacus lined with opus signinum, probably a tank for grape pressing, although both the collection vat and connecting pipe are missing. Traces of the foundation trench relating to the farm’s northern perimeter wall were found together with a few fragments of Volterran black glaze pottery dating to about the mid 2nd century B.C. The dating of the complex to the period following the colonial deduction is concordant with both the typology of the walls and the foundations. Not only, the late Republican structures are on the same northern alignment as that noted in the contemporary farms of Fossa Nera A and B, but which can also be seen in the city of Luca in the tract of wall dating to 180 B.C. which is incorporated into the western face of the della Rosa chapel.

The investigation of phase II of the farm revealed that the rooms situated to the south had floors, of which small patches survive, in which fragments of Italian sigillata pottery are embedded. In fact, from below a layer of post-deposit organic marsh silt, an opus signinum pavement of crushed and tightly packed brick and tile fragments emerged. This was similar to those discovered at Fossa Nera B.

The floors in the farms at Palazzaccio and Fossa Nera B date the beginning of phase II to the early Augustan period, at a time just after the great restructuring of circa 30 A.D. which at Luca saw the construction of the theatre in piazza S. Agostino and the public buildings which are below the present day Banca del Lavoro.

Activities continued at the Palazzaccio farm until the beginning of the 2nd century A.D. Then, in concomitance with events at nearby Lucca, there was a period of crisis and abandonment, attested by a layer of fill and collapse which seals the grape pressing tank. The presence of smooth late Italic pottery dates these events to between the Trajanic and Hadrianic periods. The abandonment of a structure identified as a silo for the maturing of products needing humidity dates to the same period. This structure was created inside the upper part of a well (discovered in 2003), which once it no longer provided water, was abandoned and filled in.

The walled structures visible to the south must be attributed to phase III, pottery finds from which are datable to the 3rd-4th centuries A.D.