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 Himera (480 BC) had taken over neighboring Sikan and Sicel lands under the tyrant Theron (488–472 BC). To forestall any conflicts between Akragas and Syracuse, Gelo and Theron married into each other's families, thus creating a united front against the Sicels and Ionian Greeks of Sicily. To counter this Doric threat, Anaxilas of Rhegion from Italy, who had captured Zankle from Gela in 490 BC, allied himself with Terillus of Himera, and married the daughter of Terillus. Himera and Rhegion next became allies of Carthage, the tyrants even built up personal relationships with the Magonid dynasty of Carthage. Selinus, a Doric city whose