Basilica di San Paolo Fuori le Mura. Basilica of St. Paul Outside the Walls is Rome's fourth great patriarchal church; it was erected over the tomb of St. Paul. The basilica fell victim to fire in 1823 and was subsequently rebuilt. This courtyard was part of the early church and was a meeting place for those who wanted to learn about Christianity. This is the second-largest church in Rome after St. Peter's.