A strong wall over 2,600 m. long, built in the years of Cassandros, protected the town. The fortifications were further reinforced by a number of towers standing 33 m. from each other. This wall was repaired once in the Hellenistic period and was rebuilt in the second half of the third century AD., when fierce barbaric raids had to be repelled. In the fourth century AD a new, but mediocre, wall was built around the Early Christian settlement, a small, faded reminiscence of the ancient town.