The sixth excavation campaign was undertaken during July-August 2007 on the site of Trebbio (Sansepolcro-AR), under the direction of the Dept. of History “E. Lepore” of the University of Naples “Federico II” and by the Research Unit on Prehistoric Ecology, Dept. of Environmental Sciences “G. Sarfatti” of Siena University, in collaboration with the Archaeological Superintendency of Tuscany. The investigations were also carried out with the assistance of the Archaeological Group of Sansepolcro (GRAS) and the Study Centre for the Quaternary Period (CeSQ). Students, postgraduates and researchers from the Universities of Siena, Naples and Rome, as well as school students from the province of Arezzo were also involved.

The settlement of Trebbio is situated on the alluvial plane on the left bank of the Tiber, at 3 km S-SW of Sansepolcro, where the river Afra meets the Tiber (300 m a.s.l.).
The latest excavation campaign looked at the area partially investigated in 2005-2006. The latter was enlarged in order to complete the excavation of a surface with a dense concentration of cobbles and pottery fragments, already denominated “cobbled surface” or “structure 2”. This led to the uncovering of the remains succeeding “structure 2” and the identification of several levels in phase with the latter.

Excavation continued in the central sector of the area on the large pit denominated “structure 1” (now known as US 393), situated a few metres south of “structure 2”.
The pit contained animal bones, including what is probably a dog’s skull, large quantities of baked-clay and numerous fragments of impasto pottery, both with coarse fabric and a finer yellowish-orange type. On the bottom of the pit was half of a cup with a curving profile and a horizontal handle which, together with all the other impasto material recovered in US 379, suggests a 6th century B.C. date.

North of pit 393 an unusual feature was excavated, the remains of a small wooden structure, that is a row of small burnt posts placed in inside a small channel on a N-S alignment (US 402-401). The structure seemed to incorporate, or intentionally respect, a grey sandstone sub-rectangular cippus (US 412), which presented clear traces of hammer work on its surfaces. South of the stone an iron knife with curved blade was found, an artifact which could convalidate a ritual interpretation of this structure.

This site is of great importance for the earliest history of the Etruscan-Italic populations. In the first place its great antiquity should be taken into consideration – dating to at least between the 8th-6th century B.C. – as should its position next to the Tiber, known as an important boundary dividing the territory of the Etruscans from that of the Italic populations of Umbrian-Sabellian descent. It was also an important crossroads and commercial centre. The settlement’s great size is an important new addition to the panorama of knowledge regarding the Italic civilizations. On the basis of surface survey it seems to occupy an area of 35-40 hectares, a dimension much larger than is the norm for Italic centres.