Our understanding of Roman urbanism relies on evidence from a few extensively investigated sites, such as Pompeii and Ostia, which are unrepresentative of the full variety of Roman towns. This article presents the results of the first high-resolution GPR survey of a complete Roman town—Falerii Novi, in Lazio, Italy. The authors review the methods deployed and provide an overview of the results, including discussion of a case-study area within the town. They demonstrate how this type of survey has the potential to revolutionise archaeological studies of urban sites, while also challenging current methods of analysing and publishing large-scale GPR datasets.