Ancient site of Gla, or Arné as Homer named it, dating from Mycenaean times. It probably wasn't a palace like Mycenae or Tiryns. More likely a fortress or safe harbor for those cultivating the surrounding plains, which were systematically drained by a network of canals.
Not much to look at today except for the remains of the massive "cyclopean" walls. Beware of snakes, as they are plentiful.
--grecodan