river sides, and, as a rule, roads pick out valleys or level ground for their natural course. For military purposes, however, it would sometimes be necessary to depart from the valley routes, and, as we shall see, the Roman roads paid no regard to these requirements.
The earliest communication between nations, as we have seen, was that of the Phœnicians by sea. They founded factories, or neutral grounds for trade, at appropriate spots all along the Mediterranean coasts, and the Greeks soon followed their example in the Ægean and Black Seas. But at an early date, as we know from the Bible, caravan routes were established between Egypt, Syria, and Mesopotamia, and later on these were extended into Farther Asia. But in Europe the great road-builders were the Romans. Rome owed its importance in the ancient world to its central position, at first in Italy, and then in the whole of the Mediterranean. It combined almost all the advantages necessary for a town: it was in the bend of a river, yet accessible from the sea; its natural hills made it easily defensible, as Hannibal found to his cost; while its central position in the Latian Plain made it the natural resort of all the Latin traders. The Romans soon found it necessary to utilise their central position by rendering themselves accessible to the rest of Italy, and they commenced building those marvellous roads, which in most cases have remained, owing to their solid construction. "Building" is the proper word to use, for a Roman road is really a broad wall built in a deep ditch so as to come up above the level of the surface. Scarcely any amount of traffic could wear this solid substructure away, and to this day
