Now, as the king was in great strait, and knew not how he should deal with the emergency, Ephialtes, the son of Eurydemus, a man of Malis, came to him and was admitted to a conference. Stirred by the hope of receiving a rich reward at the king's hands, he had come to tell him of the pathway which led across the mountain to Thermopylae; by which disclosure he brought destruction on the band of Greeks who had there withstood the barbarians. This Ephialtes afterwards, from fear of the Lacedaemonians, fled into Thessaly; and during his exile, in an assembly of the Amphictyons held at Pylae, a price was set upon his head by the Pylagorae. When some time had gone by, he returned from exile, and went to Anticyra, where he was slain by Athenades, a native of Trachis. Athenades did not slay him for his treachery, but for another reason, which I shall mention in a later part of my history: yet still the Lacedaemonians honoured him none the less. Thus then did Ephialtes perish a long time afterwards.
Besides this there is another story told, which I do not at all believe- to wit, that Onetas the son of Phanagoras, a native of Carystus, and Corydallus, a man of Anticyra, were the persons who spoke on this matter to the king, and took the Persians across the mountain. One may guess which story is true, from the fact that the deputies of the Greeks, the Pylagorae, who must have had the best means of ascertaining the truth, did not offer the reward for the heads of Onetas and Corydallus, but for that of Ephialtes of Trachis; and again from the flight of Ephialtes, which we know to have been on this account. Onetas, I allow, although he was not a Malian, might have been acquainted with the path, if he had lived much in that part of the country; but as Ephialtes was the person who actually led the Persians round the mountain by the pathway, I leave his name on record as that of the man who did the deed.
Great was the joy of Xerxes on this occasion; and as he approved highly of the enterprise which Ephialtes undertook to accomplish, he forthwith sent upon the errand Hydarnes, and the Persians under him.
The troops left the camp about the time of the lighting of the lamps. The pathway along which they went was first discovered by the Malians of these parts, who soon afterwards led the Thessalians by it to attack the Phocians, at the time when the Phocians fortified the pass with a wall, and so put themselves under covert from danger.
And ever since, the path has always been put to an ill use by the Malians.
The course which it takes is the following:- Beginning at the Asopus, where that stream flows through the cleft in the hills, it runs along the ridge of the mountain (which is called, like the pathway over it, Anopaea), and ends at the city of Alpenus- the first Locrian town as you come from Malis- by the stone called Melampygus and the seats of the Cercopians. Here it is as narrow as at any other point.
The Persians took this path, and, crossing the Asopus, continued their march through the whole of the night, having the mountains of Oeta on their right hand, and on their left those of Trachis. At dawn of day they found themselves close to the summit. Now the hill was guarded, as I have already said, by a thousand Phocian men-at-arms, who were placed there to defend the pathway, and at the same time to secure their own country. They had been given the guard of the mountain path, while the other Greeks defended the pass below, because they had volunteered for the service, and had pledged themselves to Leonidas to maintain the post.
The ascent of the Persians became known to the Phocians in the following manner:- During all the time that they were making their way up, the Greeks remained unconscious of it, inasmuch as the whole mountain was covered with groves of oak; but it happened that the air was very still, and the leaves which the Persians stirred with their feet made, as it was likely they would, a loud rustling, whereupon the Phocians jumped up and flew to seize their arms. In a moment the barbarians came in sight, and, perceiving men arming themselves, were greatly amazed; for they had fallen in with an enemy when they expected no opposition. Hydarnes, alarmed at the sight, and fearing lest the Phocians might be Lacedaemonians, inquired of Ephialtes to what nation these troops belonged. Ephialtes told him the exact truth, whereupon he arrayed his Persians for battle. The Phocians, galled by the showers of arrows to which they were exposed, and imagining themselves the special object of the Persian attack, fled hastily to the crest of the mountain, and there made ready to meet death; but while their mistake continued, the Persians, with Ephialtes and Hydarnes, not thinking it worth their while to delay on account of Phocians, passed on and descended the mountain with all possible speed.
The Greeks at Thermopylae received the first warning of the destruction which the dawn would bring on them from the seer Megistias, who read their fate in the victims as he was sacrificing.
After this deserters came in, and brought the news that the Persians were marching round by the hills: it was still night when these men arrived. Last of all, the scouts came running down from the heights, and brought in the same accounts, when the day was just beginning to break. Then the Greeks held a council to consider what they should do, and here opinions were divided: some were strong against quitting their post, while others contended to the contrary. So when the council had broken up, part of the troops departed and went their ways homeward to their several states; part however resolved to remain, and to stand by Leonidas to the last.
