mahdnc. . . . the Scavi Tour is (to me) the most awesome tour in Rome! If you haven't already, read the book "The Fisherman's Tomb" by John O'Neill.
From Google Books: A Texas oilman. A brilliant female archaeologist. An unknown world underneath the Vatican. In 1939, a team of workers beneath the Vatican unearthed an early Christian grave. This surprising discovery launched a secret quest that would last decades — a quest to discover the long-lost burial place of the Apostle Peter.