This paper presents the results of an historical and topographical survey carried out in the middle Tiber valley, more specifically in the Sabina Tiberina, in the area around Poggio Sommavilla. The survey focused particularly on the area under the present-day administration of the Comune of Stimigliano, with the aim of reconstructing the topographical layout of the Roman landscape. The field survey shed important new light on the nature of the archaic and Roman road network. In particular, as well as the Via Flaminia that runs along the western limits of the study area, another road was identified running in a broadly northeast-southwest direction, which appears to have formed the main trade route that served the area during both the archaic and Roman periods. Furthermore, the study of earlier maps, together with the evidence from the survey, has permitted the identification along the Tiber of a number of ancient ports, the positions of which were not known previously.
It is interesting to note that the settlement pattern characteristic of the Iron Age, which favoured high plateaux overlooking the Tiber, continued into the archaic period. This appears to have had a significant impact on settlement of the Roman period, in that the earliest attested Roman villas in this area are those situated next to the Tiber. The development of the ‘phenomenon of the villa’ in the area of the Sabina Tiberina from the end of the Republican period (third to second centuries BC) is consistent with the results of studies in other parts of central Italy. The study of the pottery collected from settlements of the archaic period (Colle Rosetta) and the Roman period (San Sebastiano) confirms the importance of the Tiber as a trade route for commercial exchange.