When the Persians arrived at Thermopylae in mid-August, they initially waited for three days for the Allies to disperse. When Xerxes was eventually persuaded that the Allies intended to contest the pass, he sent his troops to attack. However, the Allied position was ideally suited to hoplite warfare, the Persian contingents being forced to attack the Greek phalanx head on. The Allies withstood two full days of Persian attacks, including those by the elite Persian Immortals. However, towards the end of the second day, they were betrayed by a local resident named Ephialtes who revealed to Xerxes a mountain path that led behind the Allied lines, according to Herodotus. Herodotus has often been dismissed as a 'story teller', by Aristotle himself amongst others, and this may be a piece of folklore to create a more engaging narrative. In any case, it is impossible to determine with absolute certainty the legitimacy of Ephialtes' involvement in the battle. The Anopoea path was defended by roughly 1000 Phocians, according to Herodotus, who reportedly fled when confronted by the Persians. Made aware by scouts that they were being outflanked, Leonidas dismissed most of the Allied army, remaining to guard the rear with perhaps 2,000 men. On the final day of the battle, the remaining Allies sallied forth from the wall to meet the Persians in the wider part of the pass to slaughter as many Persians as they could, but eventually they were all killed or captured.