VIA PORTUENSIS
(Not. app.; Eins. 12. 4):the road leading to the portus Augusti constructed by Claudius on the right bank of the Tiber, at the mouth. It started from the pons Aemilius, and the first part of its course is identical with that of the via Campana. The PORTA PORTUENSIS (q.v.) of the Aurelian wall had a double arch, probably owing to the amount of traffic it had to carry (see Mon. Linc. xxvi. 417-430), but the divergence occurred a good deal further on, probably a mile from the gate. The via Portuensis went to the right into hilly country, while the via Campana kept to the valley of the Tiber. The roads rejoined at the modern Ponte Galera. See T. v. I-86.
With the growth of importance of the via Portuensis from the time of Constantine onwards, that of the via Ostiensis correspondingly decreased. It is to be noted that Procopius (BG i. 26. 9-13), who calls the road to Portus ὁμαλήν τε καὶ ἐμπόδιον οὐδὲν ἔχουσαν, and tells us how barges were dragged up the river by teams of oxen moving along it, must be describing the towpath, and not either the via Portuensis or even the via Campana, which is in many places at quite a considerable distance from the winding course of the river.