The excavations carried out during the fifth season (2019) continued to reveal important previously unknown or only partially known, topographical aspects of the Roman municipium of Trebiae. The open area excavations concentrated on sector II. Two new rooms were identified, denominated Room N and Room P.

Room N was connected to Rooms G, H, F, and I found during previous campaigns. A preliminary suggestion is that this was a public complex, whose nature remains to be ascertained. The floor was a mosaic of pink and black tesserae with marine scenes and mythological figures. Specifically, two large images of a triton and a nereid, the mythological figure of Scylla and a large horse with a fish-shaped body, all within a border of two rows of alternating geometric motifs. The various images do not seem to have been set out with a narrative intention; rather they seem to have been thought of individually, without any particular link between them.

Although the mosaic’s marine iconography suggests the association of the room in question with a bath structure, the total absence of architectural elements strictly connected to water management seems to exclude this hypothesis at the moment. However, it is possible that there was a small nymphaeum in the west wall of the room, as suggested by the presence of a finely decorated apse, characterised by a base with a moulded travertine architrave and lateral jambs with brick half-columns.

Room P was adjacent to room N and the two were connected by a small opening with a travertine threshold. Room P had a well-made opus signinum floor that presented signs of some restoration, showing its prolonged use. Three burials in earth graves, of adult and sub-adult individuals, were intercepted up against one of the room’s perimeter walls. Evidently, in its last phase of use, having lost its original function, the room was used for the burial of the last inhabitants of the site, probably in the 5th-6th century A.D.

As the research stands, it is difficult to provide a more precise reconstruction or identify with any certainty the use and function of these structures. However, the typology and construction technique of the walls suggest (a preliminary interpretation) they belong to one or more Roman domus within a settlement that was continuously occupied for a long period.
The preliminary study of the pottery, glass and coins indicates occupation on the site between the 3rd century B.C. and the 7th century A.D.