Rome Transformed' is a five-year ERC funded research project that began in 2019 with the aim of developing an understanding of Rome and its place in cultural change across the Mediterranean world by mapping political, military and religious changes to the eastern Caelian from the first to eight centuries. The project has brought together a team of specialists in non-invasive methodologies for the investigation of complex modern urban environments. Beginning with extensive archival and bibliographic research, the project is conducting detailed structural analysis of all the standing monuments in the area. This includes structures such as the Aurelian Walls, the Claudio-Neronian aqueduct and the Sessorian Palace complex. A central component of these investigations is the high-resolution geophysical prospection of the study area which covers around 13.7km2 in central Rome. The use of these non-invasive methodologies in central Rome led to several challenges, in particular the significant topographical changes that have occurred since antiquity. To the west, underneath the Basilica of Saint John Lateran, nine metres of vertical stratigraphy are preserved, ranging from Republican houses at the lower level through to the Castra Nova of Septimius Severus and the Constantine Basilica. This paper, as well as presenting preliminary results of the geophysical surveys, will also discuss some of the solutions for geophysical prospection in complex urban environments. For the study of the Eastern Caelian, the collation of information regarding previous excavations has been fundamental, which has been greatly assisted by a collaboration with the municipal authority archaeological service and access to their ArcheoSITAR database.