This survey was undertaken as part of the Roman Towns in the Middle and Lower Tiber Valley Project. The work forms part of the British School at Rome’s broader Tiber Valley Project. The survey of _Forum Cassii_ confirms the impression gained from previous work that the settlement is both small and dispersed. Work in the northern part of the site, already identified as the main focus of settlement, was disappointing, as it failed to locate further structures. However, the absence of major buildings and the total lack of surface finds suggests that the site was not a large settlement centre. Despite the small scale of survey work undertaken in this part of the site, the team examined much of the remainder of the area, so the absence of surface evidence of settlement probably can be upon. In the area to the south, the discovery of a major terrace and the line of the Via Cassia, together with a series of probably funerary monuments, enhances our understanding of the site. Finally, the enclosure to the north of the church perhaps provides evidence for the earlier medieval period.