The city wall was built from the limestone of Mount Olympus between 306 and 304 BC, under the rule of the Macedonian king Kassander. It was 2625 meters long, three meters thick and seven to ten meters high. The western side is 642 m long, the southern and northern sections each 682 m long. The eastern part of the fortification has not yet been completely excavated. At a distance of 33 meters (100 Doric feet, 32.8 cm) stood towers with a floor area of seven by seven meters. In the southern and northern wall sections were two city gates, in the western part one city gate was found.