The cliff was steep, but nowhere close to vertical. The rocks were dry, and fissures offered hand- and footholds. The tall, thin figure of Aulus led the way, taking it slowly. They never needed the pitons or ropes. Only once did Valens slip, when a projecting rock came away in his hand. Gripping with his other hand, his boots wedged in a crevice, he waited for a moment. He did not look down. Soon his heart returned to something near its normal rhythm.

Although the climb was not that demanding, Valens was relieved when they reached a wide ledge. Aulus reached down to help him up. They flopped down on a broad path which graded up to the mouth of the caves.

From where they sprawled, getting their breath back, the enclosed world of the settlement was spread out like a painting. Below were the woods. They could see the horses grazing, but their companions must have retreated to the shade. Beneath the woods were the fields; neat rectangles bounded by loose drystone walls formed by the stones lifted over generations from the thin soil. At the bottom of the valley was the village itself. The houses and the walls of the compounds were bright in the sun. The inhabitants, going about their mundane tasks, were no bigger than ants, but clearly visible. The white line of the road crawled across the vista. Beyond the village the scene was repeated, as the land lifted again. All around, the horizon was limited by the peaks of the towering mountains.

It was, Valens thought, the ideal lookout. Nothing could move in the valley without being seen.

The path on which they sat caught his attention. Its surface was hard, compacted by traffic over the centuries. His gaze followed it to the east, where it was hidden by a shoulder of the rock. Given the high and unbroken crags to the south, it must zigzag down to the floor of the valley. Probably it descended into the woods not that far from the settlement. None of the locals had mentioned its existence.

Valens heard the rasp of Aulus drawing his knife. He turned. Aulus tested the blade on his thumb, then carefully paired a broken nail.

Looking away, Valens gazed up at the entrance to the caves.

‘Do you believe in daemons?’

Aulus sheathed the dagger. ‘Socrates had a daemon.’

‘I thought that was more a philosophical image of the soul.’

‘Maybe so, maybe not,’ Aulus said. ‘Philosophers talk bollocks, but we all worship the genius of our Lord the Emperor. Yet no one seems sure if that is the divine aspect of his soul, or some supernatural guardian that watches over him.’