What was the principal port city of ancient Rome?

Ostia was the principal port city of ancient Rome, strategically located at the mouth of the Tiber River. It served as the main harbor for the city of Rome, facilitating trade and the importation of goods such as grain, which was vital for feeding the population of the burgeoning metropolis. The importance of Ostia not only lay in its role as a commercial hub but also in its ability to connect Rome to the Mediterranean and beyond, allowing for cultural exchanges and maritime activities.

While Naples and Pisa were significant cities in their own right, they did not hold the same strategic role as a port for ancient Rome. Naples was a major cultural center but not primarily a port for Rome, and Pisa, located in northern Italy, was not established as a prominent location during the height of ancient Roman power. As for Rome itself, it was the capital and heart of the empire, but it did not function as a port city in the same way that Ostia did, since direct access to the sea was limited. Thus, Ostia is recognized as the key port city that supported Rome's economic and logistical needs during ancient times.