Thwarted by Leonidas and his advance guard at Thermopylae, the Persians faced the failure of their invasion. Their mastery of intelligence and espionage now came to their rescue when a Greek traitor informed them of a way around the Greek position. The climax of the Battle of Thermopylae saw the Persian army overwhelm and wipe out Leonidas’ force. Following their victory, the Persians swept down into southern Greece and occupied Athens. But then came the turning point: the Athenian admiral Themistocles lured the Persian navy into the narrow straits of Salamis and destroyed it. The next year, the Greek resistance won two more battles at Plataea and Mycale. The Persian invasion was over.