 It also benefitted from its proximity to lake Lerna, which, at the time, was at a distance of one kilometre from the south end of Argos.Argos was a major stronghold of Mycenaean times, and along with the neighbouring acropolis of Mycenae and Tiryns became a very early settlement because of its commanding positions in the midst of the fertile plain of Argolis.Argos experienced its greatest period of expansion and power under the energetic 7th century BC ruler King Pheidon.