“I’d rather at Ravenna have a cistern than a vine
  Since I could sell my water there much better than my wine,”

and again: 

  “That landlord at Ravenna is plainly but a cheat
  I paid for wine and water, but he served wine to me neat"[1]

[Footnote 1:  Martial, Fp iii. 56, 57.  Trs Hodgkin]

This weakness would seem, however, to have been overcome by Trajan, who built an aqueduct nearly twenty miles long, which Theodoric restored, after the fall of the empire, in 524.  This aqueduct, of which some arches remain in the bed of the Bedesis (Ronco), seems to have run, following the course of the river, from near Forli, where there still remains a village called S. Maria in Acquedotto, to Ravenna.

[Illustration:  GREEK RELIEF FROM A TEMPLE OF NEPTUNE]

The great city-port thus became one of the most important and considerable of the cities of Italy, at a time when the whole of the West was rapidly increasing in wealth and population, and especially the old province of Cisapline Gaul, which had indeed become, during the pax romana, the richest part of the new Italy.  Always an important military port it was often occupied by the emperors as their headquarters from which to watch and to oppose the advance of their enemies into Italy, and the possessor of it, for the reasons I have set forth, was always in a commanding position.  Thus in A.D. 193 it was the surrender of Ravenna without resistance that gave the empire to Septimius Severus, when, scarcely allowing himself time for sleep or food, marching on foot and in complete armour, he crossed the Alps at the head of his columns to punish the wretched Didius Julianus and to avenge Pertinax.  It was there in 238 that Pupienus was busy assembling his army to oppose Maximin when he received the news of the death of his enemy before Aquileia.

And because it was impregnable and secluded it was often chosen too as a place of imprisonment for important prisoners.

It is true that we know very little, in detail, of the life of any city other than Rome during those years of the great Peace in which we see the empire change from a Pagan to a Christian state.  Those centuries which saw Christendom slowly emerge, in which Europe was founded, still lack a modern historian, and the magnitude and splendour of their achievement are too generally misconceived or ignored.  We are largely unaware still of what they were in themselves and of what we owe to them.  By reason of the miserable collapse of Europe, of Christendom, in the sixteenth century and its appalling results both in thought and in politics, we are led, too often by prejudices, to regard those mighty years rather as the prelude to the decline and fall of the empire than as the great and indestructible foundations of all that is still worth having in the world.