They seemed bold enough. One or two had spent the morning trotting right up to the edge of the mountain slope, pointing to their camp, beckoning the Greeks to battle. They were having a fine old time with an enemy perched out of reach. Yet there was no sense of tension in the Spartan ranks higher up. Aristides had clambered up to the ridge to gauge the mood there and found only order and determination. Despite the lack of food and water, that had been reassuring.

Half his Athenians seemed to have expected a Spartan battle king to march straight at the enemy, as if war were simply a matter of two lines lining up and hacking men to death until a few remained. Instead, Pausanias tied up the entire Persian force by his presence, all facing his way, waiting and watching for him to make his move. Aristides wondered if any of the Persians had slept at all for the previous few nights. They expected an attack: in darkness, at dawn or at sunset. They had no way of telling when or how it would come. He hoped it wore on them. A small voice he would not speak aloud hoped too that Pausanias knew what he was doing.

‘I see their officer,’ said the man at his side. ‘Is that the one you meant? In that strange helmet, like a piece of pottery?’

Aristides did not turn to the speaker, nor the dozen archers who crouched out of sight in a cleft of the land. He nodded, slowly.

‘That is the one. I don’t know his name, but he commanded their horsemen yesterday – and he comes closer each day. You’ll have one chance. I doubt he will risk his neck again.’

He glanced over the little group waiting with bows strung. None of them were Athenian. He had called for the best, for volunteers. These were the ones who had trotted over, now hidden in the midst of the small force of hoplites he had brought down to the foothills.

The ritual was the same each morning and evening, or had been to that point. Aristides would send out sixty or seventy young lads without armour, bearing empty skins to fill them from the stream. When they were full, each of them struggled to run back. Their safety lay in ten times as many hoplites standing guard a little further up the slope, ready to charge down and defend them.

Out on the dawn plain, Persian horsemen swirled and circled, hundreds of them, looking to hurt, to damage. They raised a huge plume of pale dust, wafting high over the plain. Aristides strained his eyes, trying to learn their signals. He knew they would come.