Acropolis (Greek ἀκρόπολις, "upper city"): the citadel of an ancient Greek town.
The acropolis of a Greek city was the fortified upper town, used as place of refuge when the city was besieged. Often, the main sanctuary was to be found on this summit: after all, it was the best protected place in town, from where the temple would dominate the region and was visible from a great distance. The military significance diminished in the Roman age, but the fortresses were reused in the Byzantine period.
Examples from the Classical age are:
- Athens: simply named the acropolis, dominated by the Parthenon
- Byzantium (occupied by the Topkapi Palace)
- Corinth: the Acrocorinth
- Thebes: the Cadmea
From the Hellenistic age:
Similar bulwarks existed outside the Greek world, like the Capitol in Rome and the acropolis of Susa. Modern archaeologists apply the expression losely for urban fortresses in the Hellenistic and Roman east (e.g., the northeast fortress of Thessaloniki.)