The folk they came across were few in number and grew ever fewer. For each, they had only one question: did they know the Dnipar? The answer was always the same: a wave of the hand upstream. ‘Further, further.’

Always further.

One night they camped at the confluence of the Dagava with a large tributary whose name they didn’t know. In the morning a swineherd approached them. Once he had overcome his amazement at the brothers’ towering height, he answered with great enthusiasm that, yes, he knew the Dnipar. But instead of further up the Dagava, he pointed up the tributary.

Whatever was the name of this smaller river, they never found it out. It grew narrower and more winding, ever more clogged with weeds and sandbars until it came to an abrupt end about four days later at the head of a broad, crooked lake fed by rock-streams with no navigable way on.

‘This is where we get out and pull, boys,’ Erlan said. ‘I hope you’re feeling strong.’

‘As an ox,’ grinned Leikr.

‘Ugly as an ox, you mean,’ Adalrik sniggered.

‘Then that makes two of us, cock-breath.’

‘All right, all right,’ said Erlan. ‘Everything on the bank.’

Willing they may have been, strong as oxen they were not. Even with the three of them, it was soon clear the knarr was going nowhere without more help. So, leaving Adalrik and Aska to guard the boat, Erlan took Leikr and headed inland. They soon saw a smoke skein curling into the sky and under it they found a small village – a miserable cluster of shacks and ox-hide tents. At first the headman was suspicious but this soon gave way to curiosity.

They led him and some of his men back to the river. He was a sharp-nosed old buzzard, grasping their predicament quickly enough – and his opportunity to make some silver – even though they could barely understand one word of his in ten. His thralls proved tough as mules, helping them drag their boat up the riverbank. Then negotiations began.

The twins’ estimate of a portage of four days would have been a blessing indeed. Instead, it took six days of butting and heaving and shoving the boat over its timber rollers, cajoling and coaxing the headman’s wretched oxen with whips and goads over the upland terrain till they were more sweat than muscle. And at long last they were sliding the hull down a silty bank into the mighty Dnipar.

In the six days past, Erlan had learned a few words of the headman’s language. When they were ready to push off, he thanked the old man and paid him his silver.

‘The big river,’ the headman intoned. ‘Runs east a while. Then south.’

‘And then the sea?’

The headman shrugged his bony shoulders. ‘It runs where it runs.’