During July, excavations were undertaken on the Iron Age site of Trebbio di Sansepolcro, with the aim of collecting data on the topography of the settlement’s western sector. With the help of a bulldozer, 10 areas were opened (trenches and test pits) in the locality of Commenda (in a field in lot 77 of the cadastral map). The trenches, circa 1.60 m wide (some were widened), revealed archaeological evidence at an average depth of 40-50 cm below ground level. In some cases it was necessary to go down to a greater depth before the remains appeared.
The excavations showed that most of the proto-historic/archaic remains were concentrated in the central and south-eastern parts of the lot. Trenches 1 and 2 in the central-eastern sector of the field produced the highest concentration of archaeological remains.

Several small cavities filled with dark charcoally soil were exposed in the south-eastern part of trench 1. In US 1 this soil alternated with dumps of large fragments of baked clay, charcoal and pottery sherds. Nearby there was a small hole (US 2) filled by an ashy layer containing occasional pottery fragments, among which a sherd from an orientalizzing pyxis.

In trench 2 the archaeological remains, situated further towards the north, were more scattered. Towards the centre of the field, an extension to the trench identified a wide strip of terrain showing evidence of occupation, US 10, rich in charcoal and heavily disturbed by recent agricultural activities. A fragment of a thin-walled black bucchero cup was collected from its surface (end of the 7th- beginning of the 6th century B.C.).
The archaeological finds dating to the proto-historic/archaic period thinned out until completely disappearing in the trenches dug in the north-eastern and north-western zones of the field.

In trenches 4 and 6, at the furthest southern edge of the field, the presence of very extensive sandy alluvial deposits was noted, which presumably corresponded to the ancient bed of the river Tiber. These deposits were cut by a large channel or hollow, whose upper fill, US 14, dated to the Roman period. The lowest, blackish clayey levels (US 17), reached in a trench with a maximum depth of 2.70 m, can be dated to the period of the settlement’s greatest development (7th-6th century B.C.). These deep levels filled a large cut in the natural, of presumably trapezoidal shape, of which an edge was identified in plan and in the exposed section. The structure may be interpreted as a large channel or feature forming a boundary to the settlement (ditch?), whose topographical and functional characteristics have yet to be defined.

The excavations documented that the western limits of the settlement of Trebbio coincide with the central zone of the field, to the west of which evidence of the settlement rapidly thins out, then disappears completely. This seems to confirm considerations made on the basis of the results from field survey and previous excavations. Furthermore, a structure presumed to be a settlement boundary was also identified, and will be investigated in coming campaigns.