Expansion of Macedonia under Philip II a significant problem, blocking the main route into Greece. However, a second route into central Greece was available. In 480 BC, during the Battle of Thermopylae, the Persian king Xerxes had sent his army via a mountain track (the "Anopea") to outflank the pass. From this track, on the western side of Mount Kallidromon, another road led off and descended in Phocis. In 480 BC, a thousand Phocian troops were stationed above Thermopylae to guard the road and prevent a Persian assault on Phocis (though they notably failed to prevent the Persians using "Anopea"). However, in 339 BC, the Greeks
Battle of the Persian Gate the most serious challenge to Alexander's conquest of Persia. Michael Wood has called the battle decisive and A. B. Bosworth refers to it as a "complete and decisive victory for Alexander". Similarities between the battle fought at Thermopylae and the Persian Gates have been recognized by ancient and modern authors. The Persian Gates played the role "of a Persian Thermopylae and like Thermopylae it fell." The Battle of the Persian Gates served as a kind of reversal of the Battle of Thermopylae, fought in Greece in 480 BC in an attempt to hold off the invading Persian forces. Here, on