They came to the Pass of Thermopylae, the sea on their right hand to the north, crisped with the bright waves of summer. It was a formidable place. To the left of them the heights of Mount Kallidromos rose up stark and sheer, a defensive wall brilliant at noon, and lit at night only by the summer starshine, for it will have been the dark of the moon when they took up their positions. The full Carneia moon that year was on 20 August.
Their right flank, then, lay on the sea and their left was protected by Kallidromos, an ideal place for a hoplite line, being unturnable at either end. It requires an effort of the imagination today to see the pass as it was at the time when Leonidas reached it. Over the centuries, the Malian Gulf has silted up and the modern coastline now lies several miles away from the scene of the action. In 480, however, the point which was chosen for the defensive line was only about twenty yards wide. There were two other places that were even narrower, one to the east and one to the west of the chosen position. The reason why Leonidas and his staff eliminated them from their strategy was that in both of them the slopes, though steep, were far from sheer. In a massive assault, such as was to be expected, their left flank might well be turned. The Persians, it must be remembered, were mountain men and accustomed to fighting over rocky conditions - far more so than any Greek hoplite, who must of necessity fight on comparatively flat ground. The Spartans, therefore, chose a slightly wider front, but one where their vulnerable left was protected by a sheer wall of rock.
There was another advantage to be gained from the site they chose. At this point, which was known as ‘The Middle Gate’, the people of Phocis at some time in the past had built a defensive wall designed to protect them from the Thessalians to the north. It was now in a ruinous condition, so the defenders immediately set about repairing it. The sulphurous springs which gave the place its name, Hot Gates, poured out - and still do - from the base of the mountain about a mile to the north-west from ‘The Middle Gate’. They presented no hazard to anyone passing along the ancient coast road, and nowadays have been diverted into some modern baths, where those whose olfactory threshold is high can enjoy them.
Xerxes and the army were still in Macedonia when the Spartans and allies began to dig themselves in at Thermopylae. He was just on the point of moving, since reports had reached him that the way was cleared for the troops to pass over the mountains into Thessaly. Just as the first columns were beginning their advance, he decided to send a small detachment from the fleet down to inspect the strait between Cape Sepias and the island of Skiathos, and then to reconnoitre the Gulf of Pagasae. This was to lead to the first naval engagement of the whole campaign, and one which did not auger very well for the Greeks. Ten fast ships, almost certainly Phoenician and possibly specifically from Sidon, were selected for the operation.
The Greeks from their naval base at Artemisium had naturally enough despatched scouts to watch the Skiathos channel where the enemy must inevitably first be seen. There were three triremes on guard, one from Athens, one from Aegina, and one from Troezen -their task clearly being not to engage any advance squadron but to report back quickly to base. They were, however, out-manoeuvred or, as seems clear, the heavier Greek vessels were no match in speed for the lighter-built and faster Phoenicians.
At the first sight of the enemy all three turned tail and fled. The Persians gave chase, and the ship from Troezen, commanded by Prexinus, was captured at once. The victors picked out the best-looking of the marines on board, took him up to the bows and cut his throat. They thought, no doubt, that the sacrifice of their first handsome Greek prisoner would aid their cause. The name of this unfortunate was Leon, which may have had something to do with his fate. [Leon means ‘Lion’, therefore possibly a very acceptable sacrifice?] The ship from Aegina, however, which was commanded by Asonides, put up a fierce resistance. A marine on board, Pytheas, distinguished himself in particular and, after his ship was boarded, continued to fight until he was almost cut to pieces. He fell at last but, as he was still alive, the Persian marines did all that they could to save his life, dressing his wounds with myrrh and binding them up with linen. When they got back to their base they displayed him with admiration to everybody there and looked after him well. The other prisoners from the ship, however, were treated as slaves’
War, then as now, was an indescribable mixture of cruelty and violence coupled with admiration, in some cases, for the courage of an opponent.
The third vessel, the Athenian, its retreat cut off, fled northward and finally ran itself aground at the mouth of the River Peneus in Thessaly. The whole crew of 200, who only got clear of their pursuers by the narrowest of margins, then made their way back through hostile Thessaly to reach Athens after a long overland march. Presumably the Thessalians let them through because sailors were worthless as hostages, not worth ransoming, and had nothing with them of the slightest value. On the other hand, they may still have been temporising and have not as yet quite made up their minds as to the forthcoming issue between Persian and Greek. Three of the pursuing vessels, we learn, ran aground on a small rocky reef in the Skiathos channel which, with seamanlike efficiency, they promptly marked for the benefit of the oncoming fleet using stone blocks to form a pillar. (The Phoenicians’ marker pylon has long since gone, but the place is clearly marked on modern charts, and shows itself by a breaking swell when the wind is in the north.) On receipt of a signal flashed from Skiathos the Greek fleet is said by Herodotus to have withdrawn to Chalcis (a run of some ninety miles). Some modern historians have thought it unlikely that the fleet would have done more than withdraw a few miles west of Artemisium, although they would certainly have withdrawn their lookouts and advance guard from Skiathos itself.
Xerxes and his staff had calculated that it would take the army some fourteen days to get itself down to Thermopylae. The fleet on the other hand, moving from the Thermian Gulf to that of Pagasae, could do the journey in two to three days. The fleet was therefore instructed to stay where it was for eleven days after the king’s departure and then get under way for the rendezvous. If Xerxes
and his staff, after all their elaborate preparations over the years and in all their efficiency on the march itself, had erred, it was in ignoring the time element. Once they had got themselves across on to the mainland of Europe there seems little evidence that they had made any great haste. Indeed, such evidence as there is suggests that Xerxes, enjoying his triumphal progress, had dallied too long. It is true that in places the nature of the terrain had delayed them (necessitating road-building, for instance), but even now, when his scouting squadron had returned with their news and he knew that the Greeks were awaiting him, he seems to have dallied. While in Thessaly he held races between his own Persian horses and the local breed, and was delighted when the Persians triumphed every time, for he had been assured that the horses of Thessaly were the finest in Greece. This seemed a good omen. In Achaea he found time to listen to local story-tellers and even diverted the army slightly to avoid a piece of ground which he had been told was sacred.
The admirals and captains of the Persian fleet may well have wished that the army could move a little faster (often a bone of contention between other navies and armies in many later years). None of them can have been ignorant of the fact that they were now into mid-August and that it would be late in the month by the time that they set sail. Even in those days without charts, written information or instruments, weather lore, transmitted orally over many centuries, will have been almost as accurate as anything that can be found in a modern Pilot for the Aegean. When vessels were relatively frail and very largely dependent upon manpower, weather conditions were all-important and none of the master-mariners in the Persian fleet can have been ignorant of the fact that, although sultry high summer was still with them, it could break at any moment. Hesiod wisely set the limit of the sailing season for sensible men to fifty days after the summer solstice. Even though the Egyptians, for example, may have been ignorant of Aegean conditions it is impossible that the Greeks from Ionia and the islands or the Phoenicians who had known the sea for centuries cannot have been aware that they were about to set out down a singularly inhospitable coast at a time in the year when the weather is likely to become unstable. Under the grande chaleur of summer all the Aegean has been gradually heating up and it requires no more than a slight change in barometric pressure to produce an imbalance. When this happens the hot air rises suddenly over the sea, lifting like a great balloon, and the cold air from the north roars down to replace it. The Delphic oracle (though often misleading and confusing) was at the same time the repository of most of the knowledge - including meteorological - of its time. ‘Pray to the Winds’ had been the last counsel given to the seemingly doomed Greeks. The Athenians accordingly offered up prayers to Boreas, God of the North Wind.
The Persian fleet sailed on time as ordered and, after one day’s voyage out, ‘they were off the part of the Magnesian country between Casthanea and Cape Sepias. On arrival the leading ships made fast to the land but, as there was not much room on the small beach, the remainder came to anchor and lay facing offshore in lines up to eight deep.’- All had gone well so far, but many of the captains, except for those who had arrived first and managed to beach their ships, had good reason to feel uneasy at their exposed position, but still they could remind themselves that twenty-four hours would see them in safety. ‘At dawn next day,’ Herodotus continues, ‘the weather was clear and calm… .’
It was that curious bright stillness which often precedes the onset of a violent north-easter. A ‘Hellesponter’ was then the Greek word for it, while today it is known as the maistro, the ‘master wind’. It can come raging out of a cloudless sky without warning, as the hot air lifts soundless to the south. (Even the modern barometer can be too slow to catch any advance changes in the air pressure.) As often as not there are no forewarning signs - no banners of cirrus or altostratus, nor any premonitory swell in advance of its coming. So it was on that day when the Persian fleet was getting under way and preparing to move on down the coast. Suddenly out of the north the wind began to pour in gale-force fury. The Persian fleet was caught on a lee shore.
Those who realised in time that the blow was coming, and all who happened to be lying in a suitable place, managed to beach their vessels and get them hauled ashore before they were damaged and before they lost their own lives as well. The ships which were caught offshore, on the other hand, were all lost: some being driven down onto the place called the Ovens at the foot of Mount Pelion and others onto the beach. A number ran aground on Cape Sepias itself, and others again were driven ashore off the cities of Meliboea and Casthanea. It was a storm of the greatest violence.
The Athenians had prayed to Boreas and the god had obliged them. Herodotus maintains that the Persians lost ‘four hundred ships, at the lowest estimate’. This, like his figures for the fleet itself, would seem to be an exaggeration. That they lost a great many is almost undeniable, as anyone who has seen that harsh coast can easily imagine. (It would be hard going to claw off it even in a well-found modern sailing boat under northerly gale conditions.) Awkward, oared triremes, with only a squaresail, would have been extremely difficult to extricate from such a lee shore and there can be no doubt that the loss was severe. Perhaps a quarter may have been destroyed, but a loss of 400 fighting vessels would have amounted to nearly half of the front-line fleet: something which would have been unacceptable and which would have led to the abandonment of the naval campaign. The fact that the Persians regrouped, made good their storm damage, and later proceeded relentlessly on their way does not suggest a shattered fleet. The gale lasted unabated for three days - a long blow for August when such storms, though fierce, are usually over in about twenty-four hours. (At a later date the Athenians remembered how Boreas had answered their prayer and built him a shrine by the River Ilissus.)
It is clear that the Greek allied fleet sat out this storm tucked well under the lee of Euboea, so Herodotus’ statement that they went as far south as Chalcis may not be wrong, although they need not have gone anywhere near as far away to find a good lee under the island. One suspects that they went a little south of the latitude of Thermopylae and then took shelter close under the western coast of Euboea. Green, however, believes the Herodotean source and thinks that Themistocles deliberately went down into the narrows by Chalcis in the hope of inducing the Persians to follow. They would then have found themselves in unfamiliar, constricted waters, where their numbers would not have been able to tell, and where the slower but heavier Greek triremes could have done to them what they were, indeed, later to do at Salamis. This is quite possible, but what is really significant is that the ‘Hellesponter’, which did such damage to the invasion fleet, left the allies completely untouched.
Even before the storm had blown itself out the Greeks had informed reports of the destruction of a great number of the enemy from their watchmen in northern Euboea. No doubt much wreckage was coming down on the great rollers past Cape Sepias and through the channel between Skiathos and the neighbouring island of Skopelos - an area known for good reason to this day as the ‘Gate of the Winds’. ‘On hearing the news, they offered prayers of thanksgiving and libations of wine to their saviour Poseidon and made all speed back to Artemisium in the expectation that there would be few ships left to oppose them.’ In this they were to be disappointed for, as they headed north for their station, they could see great numbers of ships rounding Cape Sepias and turning up into Aphctae just within the Gulf of Pagasae. It is possible that if they had been quicker in their return or had not lain so far away they could have caught the main body of the Persian fleet at this point and provided the battle that Themistocles sought. As it was, they did have one piece of luck, for fifteen stragglers coming up behind the main body mistook the Greeks for their own fleet and made to join them - only to be rounded up and captured. Since they were a mixed squadron, some of them Ionian Greeks whose triremes would have been almost identical, it is not so surprising that this mistake took place. One of the captains, who was from Paphos, admitted during interrogation that out of twelve ships from his Cypriot squadron eleven had been lost in the storm off Sepias. Greatly heartened by this news, and by the general picture that they obtained of the storm-battered condition of the enemy fleet, the allies sent back all the prisoners to their headquarters at the Isthmus of Corinth.
At the time of the great storm, the Spartans and their allies had been consolidating their position at Thermopylae. Placed as they were in that narrow pass close to the sea’s edge even the most unobservant of landsmen could not have escaped noticing - and feeling - the cut of the wind and the roar of the sea. They knew that the Great King was coming, for some of the wrack of his advancing fleet must have siphoned past the north of Euboea and been reported. The gale will have struck their narrow ledge of land and hurled upwards over the mountain that protected their inboard flank. Spray will have splattered over the sea-edge, the cauldrons with their flames will have had to be protected, and the scarlet fighting cloaks drawn close over the waiting men.