 Formerly, it was erroneously, but generally accepted, that the southern walls of St. Peter's Basilica rested on the northern walls of Nero’s Circus, and that a street ran north of the circus under the basilica (see figure).Excavations of the basilica and surrounding area, however, have shown that this was not entirely correct.An excavation in 1936 in the Piazza San Pietro discovered traces of a road that may be the post-Constantinian Via Cornelia.