The city of Rome is a museum. There probably is not a single building in the Centro Storico of Rome that is not built on top of the location of a former Ancient Roman building. What I am interested in here are churches that are either built within the structure of an ancient Roman building, or there are elements of Roman buildings still existing underneath the existing church structure.
There are some churches that have ancient Romen structure within the fabric of the building that only an expert can identify. Those churches are not listed here. Most of the churches listed here have crypts containing the Roman structures that can be visited. For instance, San Clemente has three levels of structures below the existing 8th century church.
