In the north of Cambria during the spring, you can experience the weather of all four seasons in the space of one hour. Some say that this is due to the permeable border between that land and Uffen but in his Historia et Topographia Alpium my late and much missed mentor Marcus Gaius Sabeno makes the observation that on the slopes of a mountain, showers of hail and sleet can come as if from nowhere, despite clear blue skies. With Betws-y-Coed in the lee of the prevailing direction of the winds as they blew across the ridges of Snowdon, my belief is that the region is subject to the same sudden changes of weather as the Alps and that, for once, magic is not the issue.

As he followed the two Romans, who were on foot and leading their horses along the western bank of the River Conwy, Arthyr found it necessary to pull up the hood of his cape and huddle into it against a bitter flurry of hail. Yet before he had reached the next bend, he was walking through blocks of morning sunshine that were broken up by the long shadows from the beech, ash and oak trees that covered the slopes to his right.

There were three figures waiting at the bridge at Caer Llan and Arthyr knew from a long way off that they were his friends Merilyn, Gawain, and Netanya: a tall, dark girl; a solid youth; and a smaller, fair girl. It warmed his heart that Gawain and Netanya should have risen so early just to say farewell.

‘What’s this?’ asked Alerus as their earthen path took them down the final curve that led to the stone and wood bridge.

‘Merilyn is coming with us.’

‘Is that right?’ The older Roman looked at his officer, who shrugged. Then he turned back to Arthyr. ‘Is she your girl?’

Arthyr chuckled. ‘Merilyn? She’s no one’s girl. You’ll see.’

‘Then what’s she coming for?’

‘She’s a magician, nearly as powerful as me. And more knowledgeable.’

‘Two magicians. The empress will be pleased, won’t she?’ Alerus sounded anxious as he checked with Sapentia.

‘Certainly,’ the legate replied. ‘But why does Merilyn want to leave her home for this journey? As I understand it — and admittedly my understanding may be flawed — you are not inclined to help Rome. And you, Arthyr, are only here because your village insisted that you come with us.’

‘She’s not like me. For a start, she loves learning and has learned all she can here. And then, she wants to help me, as my friend, to face whatever dangers lie in my future.’

‘I see,’ said Sapentia, ‘well that is indeed splendid news. At least, I think so. One can never be quite sure of the thinking of the empress. It is just possible she intended to limit the presence of barbarians in the Roman army to one person only. Still, it certainly makes me feel safer on these dangerous roads that I will have two magicians as my escorts.’

On the utterance of the word ‘barbarian’, the older Roman shot Arthyr a glance, presumably to check whether he had taken offence. Arthyr had not. In fact, it amused him that the iron-clad officer who was so cut off from the spirit world should consider him the barbarian. Sapentia could not listen to lively morning conversations of the birds; had no notion of the inner life of the trees, or the fungi, or the flowers. The fly that she brushed from her cheek was to the Roman nothing more than an irritant. Arthyr held up his hand and asking the light breeze for assistance, drew the fly towards his fingers. When the fly landed on his skin and danced around on his palm, Arthyr shuddered with the impressions that he allowed to run through him.

Lust. Eggs. Breeze. Male? Eggs. Sugar. Sweat. Music. Light. Horse dung! Lust. Eggs. Male. Freedom. Light. Warmth. Lust. Male!

She jumped up from his palm, rubbing her legs eagerly, darting in and out of the sunlight to initiate a mock battle with a potential mate.

They arrived at the bridge, the hooves of the Roman horses banging down loudly onto the wooden planks. Arthyr strode up to Merilyn and rested his hands on her cloaked shoulders. ‘Thank you Merilyn. Truly, thank you. I know this must have been hard on you.’

‘It was. But if I’d have stayed here, I would have been jealous. Every night I would have wondered about the new places you were visiting and the new people you were meeting.’

‘And thank you too.’ Arthyr let his arms drop and turned to Gawain and Netanya, ‘I really appreciate you coming to see us off.’

‘Arthyr?’ Netanya smiled at him.

‘Netanya?’

‘Why do you think we have these backpacks?’

For a moment Arthyr wondered what gifts his two younger friends were offering to him. Then he realised with a rush of warmth (arising from both a sense of shame at his own slow-wittedness and of pleasure at the thought of not losing his friends) that Gawain and Netanya intended to come on the journey too. Well, why not? Insofar as Merliyn tended to be a rather dull companion, their presence would make the journey a lot more fun and interesting.

‘You’re coming!’ And when Gawain and Netanya nodded, Arthyr gave them both a hug.

‘What’s this now?’ asked Alerus.

‘We’re joining you.’ Gawain hitched up his backpack. ‘Let’s go. I can’t wait to see Rome.’

The sergeant rubbed his unshaven beard, a troubled expression on his face. ‘What do you think, legate? How well will this go down back at the palace?’

Arthyr turned to look at the young officer. She couldn’t object, could she? And if she did, why he’d refuse to move on without his friends.

‘What are your names?’ the legate sounded friendly.

‘Netanya.’

‘Gawain.’

‘Well, Netanya and Gawain, I’m Sapentia and this is Alerus. You may join us, but I’m sorry to say our destination — that is, your destination, since I will be going to Rome — is not our great city, but Aventicum. Your magicians are going to the training camp there, to learn their place in the army.’

‘Aventicum?’ repeated Gawain, somewhat disconsolately. ‘I’ve never heard of it.’

Sapentia waved her free hand, ‘It’s near the Alps, quite beautiful. It’s a lovely town.’

‘For thieves, whores and charlatans,’ muttered Alerus, too low for his legate to hear, but Arthyr caught the comment.

‘Fair enough,’ said Netanya, ‘I don’t really care. I just want to see more of the world than our village.’

‘Then shall we carry on?’ asked Sepentia and began to lead her horse forward.

‘Wait! We have to depart properly.’ Merilyn looked all around, carefully, causing Arthyr to note the black, fast-flowing river, the moss-covered rocks along its banks, a scent of ferns, the drift of low-lying, rain-streaked clouds. As always, Merilyn was right to be methodical. But as always too, Arthyr found the waiting tedious.

All the local spirits were friends of Arthyr, or, at least, acknowledged their obligations to him. He could leave on a long journey without the slightest care. For the others, however, the taint of a river’s curse, a pathway’s indignation, or a forest’s hostility could mark them for weeks.

While the Romans watched with growing curiosity, Merilyn tossed several furry pellets — silver birch seeds — into the air. She knelt beside the largest stone of the bridge, where it was anchored, and leaned her head against it. Then, she vaulted lithely down to the water’s edge and picking up two handfuls of water, scattered the silver drops around her.

Arthyr yawned.

‘What’s she doing?’ whispered Sapentia, ‘magic?’

‘Not really.’ Arthyr shrugged.

‘She’s trying to hear the spirits, without having to cross over to Uffen to talk to them,’ It seemed that Netanya was not angry at the Romans and sounded keen to provide them with an explanation. Too keen. Although Arthyr had resolved to be civil, he certainly was not going to assist a possible enemy in their understanding of Uffen. The Romans had conquered this world and but for the fact that powerful, uncontrollable spirits existed in Uffen, would have conquered that world too.

‘And what does she want to talk to them about?’ asked Sapentia.

It seemed that Gawain too was inclined to be helpful to the Romans, for he added, ‘we need their good will or our journey will be cursed.’

‘Oh, I understand; how interesting.’

When Merilyn came back up the to the bridge, she ran a damp hand through her long brown hair, drawing it away from her face. ‘It is geas for the same number of men and women to cross the river in a group today and it is also geas to take the eastern path while the moon is still in the sky.’

‘Geas?’ asked Sapentia, looking around as though confirming to herself that their party consisted of three men and three women.

‘“Forbidden”, wouldn’t you say?’ Netanya looked at Gawain.

‘More like, “bad luck”’

‘You’re right.’

‘Don’t worry about it.’ Arthyr patted the Roman officer on her shoulder, seeing the concern in her face. The iron beneath her cape almost stung his hand and contact with it caused his sense of the richness of the environment around him to dimmish rapidly. He took a step away from Sapentia and blinked several times before continuing, ‘so many matters are geas that you can’t take a step without offending one spirit or another.’

Merilyn shook her head. ‘Don’t mock, Arthyr. The Conwy is powerful. She, at least, we must propitiate. Throw something valuable to her.’

Instinctively, Arthyr’s hand went to the pine necklace that Merilyn had made him.

‘Not that.’

‘Then this.’ He took out the magical piece of silver that the Seren Stone had given them yesterday. It was a shame to lose it, even if Arthyr didn’t know what use it might have. But Merilyn was right. It was best to have the spirit of the river approve of their journey.

‘Oh,’ said Gawain, as Arthyr drew back his hand. ‘Must we?’

‘We must,’ and he threw the silver nugget out from the bridge and into the river at a point where there was a lively set of ripples. It entered the black water with a cheerful, plopping sound.

‘Now,’ announced Merilyn, ‘we can set out. But we have to take the longer road when we get to Pen Llywn.’

It seemed to Arthyr that tone of the river had become rather more cheerful, that butterflies now played in the sunlit air where they had previously rested in shadows and that the chives and garlic in the grass around them gave off enervating scents. It was time to set forth and the land and the river wished them well on their long journey.

The path they walked had been made by carts: two parallel brown lines against a green and yellow background of grasses that rose to knee height. Arthyr and Merilyn led the way, then came Gawain and Netanya, then Alerus and Sapentia walking ahead of their horses. It occurred to Arthyr that the whole group had formed a line of males who walked along the left track and a line of females who walked along the right. This probably had a meaning, but Arthyr didn’t care to explore it. Rather, he was enjoying the thought that Gawain and Netanya were coming too. Exile was a lot less daunting a prospect when your friends were with you.

‘Did you dream last night?’ asked Merilyn.

‘I did. Not with any pleasure. For everyone I loved lay dead on an unlit pyre while I played the most haunting, sorrowful music.

‘And I found myself singing in a chamber full of cursed nobles, who could not rise from their stone seats. Even when my voice was worn through and my head was sagging with tiredness, I could not stop. And my song was of betrayal.

‘What does this mean?’ Arthyr glanced at Merilyn, who was walking in a tight, efficient fashion, eyes on the ruts ahead so that she could avoid the muddiest places.

For several steps Merilyn said nothing, then she lifted her brown eyes to Arthyr’s, ‘I think at least one god is interested in our journey and wishes to warn us that it might not end well.’