At the beginning of the classical period Tiryns, like Mycenae, became a relatively insignificant city. When Cleomenes I of Sparta defeated the Argives, their slaves occupied Tiryns for many years, according to Herodotus. Herodotus also mentions that Tiryns took part in the Battle of Plataea in 480 BC with 400 hoplites. Even in decline, Mycenae and Tiryns were disturbing to the Argives, who in their political propaganda wanted to monopolize the glory of legendary (and mythical) ancestors. In 468 BC Argos completely destroyed both Mycenae and Tiryns, and—according to Pausanias—transferred the residents to Argos, to increase the population of the city. However, Strabo says that many Tirynthians moved to found the city of Halieis, modern Porto Heli.