 The central gods of the Acropolis of Athens were "Poseidon Erechtheus" and "Athena Polias", "Athena patron-guardian of the city".The "Odyssey" (VII.81) already records that Athena returned to Athens and "entered the strong-built house of Erechtheus".The archaic joint temple built upon the spot that was identified as the "Kekropion", the hero-grave of the mythic founder-king Cecrops and the serpent that embodied his spirit was destroyed by the Persian forces in 480 BC, during the Greco-Persian wars, and was replaced between 421 and 407 BCE by the present Erechtheum.