The eastern half of the Mediterranean was the world of the polis. Here for example, in the region that Constantine knew best, between the northern shores of the Aegean and the lower Danube were cities such as Philip-popolis, Traianopolis, Hadrianopolis, and Diocletianopolis commemorating great rulers who founded or, by extensive building and a change of name could be said to have re-founded them. But the trip to Rome in the early summer, lasting many weeks, must have reminded him of the remoteness of the capital. Emotional and religious reasons for abandoning Rome were very strongly reinforced by others of a different kind. In equipoise, the Mediterranean world had once rested in Italy. The emperor improved the water supply by means of a new aqueduct, and granted exemption from munera to property owners abutting it, in return for their labor to keep it in good repair. The initial impetus, however, was Constantine's, and made a deep impression on his near contemporaries.