Following his victory at the Battle of Thermopylae, Xerxes sacked the evacuated city of Athens and prepared to meet the Greeks at the strategic Isthmus of Corinth and the Saronic Gulf. In 480 BC the Greeks won a decisive victory over the Persian fleet at the Battle of Salamis and forced Xerxes to retire to Sardis. The land army which he left in Greece under Mardonius retook Athens but was eventually destroyed in 479 BC at the Battle of Plataea. The final defeat of the Persians at Mycale encouraged the Greek cities of Asia to revolt, and the Persians lost all of their territories in Europe; Macedonia once again became independent.