The barber was wearing his excitable look. 'Is Veleda part of your mission?' he hissed. His wide-eyed simplicity was beginning to afflict me like a stitch in the side when you're running away from a mad bull.

'Women I can handle. But I don't do Druids!' It was a line. Two of us knew it, yet poor old Xanthus looked impressed.

I had to act fast. Our barge was approaching the great bridge at Moguntiacum; we would soon berth at the quay. I gave the pedlar a thoughtful glance. 'If somebody wanted to contact Veleda, would it be possible to get a message to this tower of hers?'

'Could be.'

Dubnus looked disturbed by the suggestion. I made it plain I was speaking with some authority, and told him not to leave town.

The pedlar assumed the air of a man who would leave town exactly when he wanted to, and without telling me first.

PART THREE:

October, AD 71

': above all the Fourteenth, whose men had covered themselves in glory by quelling the rebellion in Britain.'

– Tacitus Histories

Moguntiacum.

A bridge. A tollbooth. A column. A huddle of civilian huts, with a few handsome homes owned by the local wool and wine merchants. All dominated by one of the Empire's biggest forts.

The settlement stood just below the confluence of the Rhenus and the Moenus waterways. The bridge, which joined the Roman side of the Rhenus to huts and wharfs on the opposite bank, had triangular piers thrust out to break the current, and a wooden rail. The tollbooth was a temporary affair, about to be superseded by a massive new customs-post at Colonia Agrippinensium. (Vespasian was a tax-collector's son; as Emperor it coloured his approach.) The column, erected in the time of Nero, was a grand effort celebrating Jupiter. The huge fort declared that Rome meant business here, though whether we were trying to bluff the tribes or convince ourselves was open to debate.

My first disappointment was immediately thrust on me. I had been telling Xanthus he could busy himself setting up shop with his razors among the canabae. Most military establishments grow a thicket of booths, a shanty-town fringe that hogs the outer walls, offering the troops off-duty entertainment of the usual sordid kinds. It springs up when the baths are constructed outside the fortress as a fire precaution, after which breadshops, brothels, barbers and bijouteries rapidly collect-with or without licences. Then the inevitable camp-followers and the soldiers' unofficial families arrive, and soon the extramural clutter swells into a civilian town.

At Moguntiacum there were no booths.

It was a shock. We could see where they had all been cleared. The operation must have been swift and thorough. A mound of bashed-in shutters and splintered awning poles still stood nearby. Now bare ground surrounded the fort, forming a wide defensible berm from which the turf walls rose a clean eighteen feet to the watch-towers and patrol-track. Among the visible defenses I counted one more Punic ditch than usual, and in the midfield a fatigue party was planting what the legions call a lily garden; deep pits dug in a quincunx pattern, set with sharpened stakes, then covered with brushwood to disguise their whereabouts-a savage deterrent during an attack.

The civilians had been deposited way back beyond the outer ditch, and even a year after the Civilis Revolt no re-encroachment was allowed. The impression was stark. It was meant to be.

At the fort itself, instead of the usual organised but easy-going atmosphere of an army in peacetime, we soon grasped that this army sketched in its civic role with a light hand. Its gestures to the local community were mostly obscene.

The barber and I counted as locals until we proved otherwise. When we presented our persons at the Praetorian entrance, even Xanthus stopped twittering. We had to leave our horses. There was no making ourselves agreeable to bored sentries inside the guardroom; we were detained in the square chamber between the double sets of gates, and it was plain that if our story and our documents failed to match, we would be pinned up against a wall by a nine-inch javelin-tip and vigorously body-searched.

The atmosphere upset me. The jolt reminded me of Britain after the Boudiccan affair. That was something I had intended to forget.

We were passed in, however. My docket from the Emperor aroused suspicion but worked the trick. We were eyed up, listed, given order to go directly to the Principia, then allowed through the inner gates.

I myself was ready for the size and scope of the immense interior, but even being born and bred in the labyrinthine corridors of Rome's imperial court had failed to prepare Xanthus for this. Moguntiacum was a permanent fort, and a double one at that. With two legions stationed there, almost everything was in duplicate. It was a military city. Twelve thousand men were packed inside, with enough stores, smithies and granaries to withstand months under siege-not that that had worked for the poor devils attacked by the rebels at Vetera. Within the base, the two commanding legates would occupy minor palaces designed to reflect their grandeur and diplomatic standing; the housing stock for the twelve young military tribunes who supported them would make the best villas in most Italian towns look mean; and even the commissariat buildings, where Xanthus and I were heading, were dramatic in their blunt, military way.

We came out from the cold shadow of the rampart walkway. With the guard-towers of the gatehouse looming overhead, we had first to cross the perimeter road. It was eighty feet wide. The perimeter track, which was designed to give protection from missiles as well as provide ready access to all parts of the fort, was kept well clear of obstruction. I made a mental note that the Fourteenth Gemina must take half the credit for the immaculate housekeeping, though they probably made their lesser colleagues empty the rubbish skips and sweep the roads. Stacks of spare javelins were stored handy for the ramparts, along with piles of heavy shot and field ballista bolts, but there were none of the roaming beasts or the litter of wagons that you often see. If the sacred chickens were allowed free range, it was not on this side of the fort.

I towed the barber past the endless barrack blocks: nearly fifty pairs (though I can't say I counted), each housing a hundred and sixty men in groups of ten, with a double set of centurions' quarters at one end of every block. Adequate space for the legionaries, plus more cramped quarters for their native auxiliaries-not that that applied to the Fourteenth at present, since their eight famous cohorts of Batavians had defected to the rebels: Vespasian would not be replacing them until I made my report.

Xanthus was already awed by the atmosphere; I merely felt a throb at re-encountering the familiar. To me the fort had a daytime, half-empty feel. Many of the troops would be in training or sweating on fatigues, others on their monthly ten-mile route march in full kit. Most of the rest would be on local patrol, and it would be no mere exercise.

'Impressed, Xanthus? Wait until the camp's full this evening! Then you will have the unique experience of being among twelve thousand men who all know exactly what they are doing!' He said nothing. 'Are you thinking of the potential in twelve thousand stubbly chins?'

'Twelve thousand flavours of halitosis!' he responded valiantly. 'Twelve thousand variations on "the girl I stuffed last Thursday". And being warned not to nick twelve thousand different wens!'

We reached the main thoroughfare. 'Xanthus, in case you get lost, try to remember the most important street is this one. It's called the Via Principalis. It's a hundred feet wide; even you can't miss the thing. Take your bearing now. The Principalis bisects the camp crossways between the Sinister and Dexter Gates, and the Via Praetoria meets it at right angles at the HQ. The headquarters always face the enemy, so as long as you can see which way the slingstones are flying in, you can orientate yourself in any fortress in the world:'