If Aenon was the place where John baptized last, immediately before his imprisonment, then we must look for it either in Galilee or Perea: for in one of those places it was where he began his acquaintance with Herod. For however St. Luke, speaking of Herod, mentions Galilee only within his tetrarchy, Luke 3:1, yet Josephus tells us, that "both Perea and Galilee were under his jurisdiction." Where then shall we begin his first acquaintance with the Baptist? I had once inclination to have fixed it in Galilee; but whilst I consider better that Herodium was in Perea, and very near Machaerus, John's prison, that seems the more probable.
Josephus, speaking of Herod the Great and his stately buildings, hath this amongst other things: "He fortified a castle upon a hill towards Arabia, and called it Herodium, after himself." Where, by Arabia, you are to understand the land of Moab; and he seemed to have fortified that castle, as a bulwark against the Moabitish Arabs.
The same Herod that built it is buried there, as the same Josephus tells us; where, describing the funeral pomp, he gives this account: "After those followed five hundred of his own domestic servants, bearing spices. His body was brought two hundred furlongs" [from Jericho where he died] to Herodium, where, according to his own appointment, he was interred. But, in Antiq. lib. xvii. cap. 10, "They came to Herodium eight furlongs; for there he had ordered his funeral solemnities." At first sight, here is an appearance of a slip in history: but it is to be understood, that from Jericho to Herodium it was two hundred furlongs, that is, twenty-five miles; but Herod's burying-place was eight furlongs from Herodium, a common distance for burying-places to be from cities.