As he reached the gate tower and began to climb, he heard a familiar laugh.

‘Hello, husband.’ Claudia Enica was dressed for riding, with loose Parthian trousers tucked into the top of her boots. Bran and Minura were with her, and he had insisted that they stay at her side, even though the boy had wished to serve as his personal guard. ‘I doubt that the Silures can sing, but you can always mime the words.’

‘You should be at your post, my queen,’ Ferox spoke mildly. Outside the principia, Maximus was in charge of the remaining auxiliary horsemen and the queen had a band of thirty Brigantes with their horses ready. Their job was to rush to any weak spot, especially if the enemy made it through one of the gates. Vindex was in charge of a score of Carvetii stationed so that they could cover the rear gate, which it was hard for the rest to reach. Ferox missed having his old friend beside him, but wanted someone he could rely upon to do the job.

As he glanced away to smile at the other men, the queen stuck her tongue out at him like a little girl. Men sniggered, especially when he turned back and she took on a look of studied innocence.

‘Shall we all go and sleep, while those cowards outside pluck up the courage to attack us?’ she asked.

‘Soon, lads, they are coming soon,’ Ferox happened to look as the big engine the Dacians had placed behind a mound of sacks some two hundred paces away loosed with a sharp crack. After a moment there was a pounding thump below them and the boards underneath his feet quivered.

‘They are shooting at the gate,’ the queen told him. ‘Have been at it for an hour. There are cracks, but for the moment it is holding.’

Petrullus shook his head. ‘The Romans should learn from the Brigantes. Even your people would not build a fort whose gate could be approached – or be shot at – in a straight line. The army would do the same in a marching camp, so why not here?’

The answer was that the Romans never expected to defend a fort like this, least of all against an enemy with artillery and some knowledge of siege craft. That was why the towers were set back and did not project outwards and no one worried too much about defending gateways.

‘Send men to bring up the carts from the fabricae,’ Ferox said. ‘And anything else to make a barricade in case they do smash the gates.’

There was silence and Petrullus broke into a grin. ‘The queen has already given the orders.’

Enica made a show of preening. ‘I do have my uses, you know.’ She paused. ‘Of course, I had forgotten that Vindex was not with us.’

Ferox was not listening. As he watched, some of the Dacians around the ballista turned and ambled away. Others appeared to take their place.