The naturally fortified site of the Acropolis is accessible only from the west. Both the Mycenaean fortress and ancient sanctuary were accessed from here, just like the modern archaeological site is today. The hill was first fortified in the Mycenaean period and traces of this early wall are still visible, particularly to the southeast of the Propylaia. The walls visible to this day were erected after the Persian Wars in the first half of the fifth century BC, under Themistokles (north wall) and ...