MARTYRDOM OF PAUL
Paul was beheaded, according to tradition, on the Ostian way, at the spot now occupied by the Abbey of the Three Fountains. The fountains, which are said to have sprung up at the spots where Paul’s head struck the ground three times after the decapitation, are still shown, as also the pillar to which he is supposed to have been bound! In the fourth century, at the same time that Peter’s remains were transferred to the Vatican, Paul’s remains are said to have been buried in the Basilica of St. Paul, which occupied the site now marked by the church of San Paolo fuori le mura. There is nothing improbable in the traditions as to the spot where Paul and Peter met their death. They are as old as the second century; and while they cannot be accepted as indisputably true (since there is always a tendency to fix the deathplace of a great man even if it is not known), yet on the other hand if Peter and Paul were martyred in Rome, it is hardly possible that the place of their death and burial could have been forgotten by the Roman church itself within a century and a half.

(1890). Eusebius: Church History, Life of Constantine the Great, and Oration in Praise of Constantine (Vol. 1).