Final report of a surface survey project conducted in central Italy during the early 1980's under the direction of Edith Wightman. The few known sites in this region were revisited and a restricted amount of systematic intensive survey was carried out to discover new sites and to trace ancient roads. Innovative features of the methodology include the collaboration of a geomorphologist to explore the relationship of settlements to soils and local geology. Whilst the book traces the history of the valley from Prehistoric to Medieval times, it concentrates on the Roman period with 3 chapters on communications, settlement patterns and society, and economy and the environment. It will provide useful comparative material to survey projects in other parts of Italy.