THE WALLS
The walls were built around the city to protect it from its enemies .
� The first fortification was built by King Cassander in 315 B . C . E . They have been rebuilt and repaired many times over the centuries , especially by Emperor Theodosius the Great ( 379-395 C . E .). They encircled Thessaloniki from the Eptapyrgion and the Citadel to the seafront .
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