Macro waited until there was complete silence again. ‘Officers and men of the legions are all expected to complete route marches. It is a minimum standard and applies to all, regardless of rank. There is no excuse for any man here failing to finish the march.’ He paused and then strode back to the front of the column, a short distance ahead of Cato and the other officers. ‘Column! Prepare to march . . . March!’

Macro paced forward, followed by the rest, four ranks abreast. He led them across the training ground and down the rough track that joined the Nile road. Even this early in the morning the farmers and merchants who were making their way into Diospolis Magna to sell their wares were on the road and they hurriedly pulled aside as the legionaries turned right and began to head north, along the road that followed the course of the Nile.

A few boats were already out, the skiffs of fishermen rowing across the current to inspect their nets, and the larger broad-beamed vessels that carried goods up and down the great river. On the far bank was a thin strip of green vegetation and then the rocky mass of the lifeless mountains rising above the desert.

An hour after the column had set off, the sun had risen over the horizon and the pale yellow disc hung in the haze like an eye surveying the ribbon of water and crops that threaded its way across the great desert of northern Africa. Cato had settled into an easy rhythm; and an early ache that had started at the bottom of his back had faded away and he was starting to feel confident about completing the march. Sweat pricked out from his scalp, saturating his felt helmet liner, and every so often a trickle escaped, coursing down his brow, and he blinked it away rather than transferring the javelin to his shield hand so that he could mop his brow.

Glancing round he saw that some of the officers were already struggling to keep up with the pace. The nearest, a centurion from the First Cohort, was puffing out his full cheeks as he laboured under his kit. One of Macro’s training optios fell into step beside him.

‘Come on, sir. Put some bloody effort in! I’ve seen old men march better than that.’

The centurion clamped his lips together and struggled on. Cato turned back, feeling slightly guilty over his plan to break men like that centurion. However, if the man made it through the day then there was obviously more to him than met the eye - though given his girth, Cato thought wryly, that would be something of a challenge. Up ahead, Macro led the way, striding steadily down the road without the slightest sign of tiring.