Either way, the Duomo di Milano is Italy's biggest cathedral, since St. Peter's in Rome has no bishop and therefore qualifies as a church or "basilica," per its name. "Once you step through the ...

St. Peter's Basilica There are nearly as many cathedrals in Rome as sculptures, but show kids a few tricks at St. Peter's and they'll be engaged. At the largest church in Christendom, designed by ...