Routes. Roman sailors were never adept at handling the high seas and always maintained a profound fear and respect for the potential violence of the Mediterranean. They, like most sailors from other periods of antiquity, preferred to stick to the coast, leaving the sight of land only when it was necessary. To the best of their ability, they limited their journeys to the calmer summer seasons and avoided travel during the unpredictable winters. Cities that were located on excellent natural harbors thus grew quickly in population, as the business of sheltering ships, both military and commercial, required and attracted a large amount of manpower. Two of the three next largest cities of the empire, after Rome, were harbor towns: Alexandria and Ephesus; the third, Antioch, was just fifteen miles from the sea, connected by the Orontes River. Inland population centers, naturally, were also...