Henry Tiptree had the glossy polish that the best English boarding schools can sometimes provide. Such boys quickly come to terms with bullies, cold showers, corporal punishment, homosexuality, the classics and relentless sport, but they acquire the hardness that I'd seen in Tiptree's face. He had a mental agility, plus a sense of purpose, that his friend Dicky Cruyer lacked. But of the two I'd take Dicky any time. Dicky was just a free-loader, but behind all the haw haws and the schoolboy smiles this one was an expensively educated storm-trooper.

As I crossed the salon, with Tiptree's whole weight upon me, I swayed and so did the mirror, the floor and the ceiling, but I steadied myself again and paused before going past the door that led to Lisl's room.

Her record was still playing and I could imagine her propped up amid a dozen lace pillows nodding her head to the music:

Make my bed and light the light,

I'll arrive late tonight.

Blackbird, bye-bye.

It was cold. Featureless grey cloud stretched across the flat countryside as far as the horizon. Rain continued relentlessly so that the last of those villagers who'd been huddled in cottage doorways waiting for a respite now hurried off and got wet. All the gutters were spilling and the rain gurgled down the drainpipes and overflowed the drains. Slanted sheets of it rebounded from the cobblestone village street to make a phantom field of wheat through which occasional motor cars or delivery vans slashed their way like harvesters.

The message from Werner had told me to come to the Golden Bear, and I had come here, and I had waited two days. On the second day a young Oberstabsmeister had arrived at breakfast time. I recognized the dark green VW Passat station wagon. It bore the badge of the Bundesgrenzschutz. For West Germany had border guards too, and one of their jobs was investigating strangers who came to border villages and spent too much time staring eastwards at the barbed wire and the towers that marked the border where people on excursions from the German Democratic Republic got shot dead.

The border guard NCO was a white-faced youth with fair hair that covered the tops of his ears and curled out from under his uniform hat. Tapers,' he said without the formality of a greeting or introduction. He knew I'd watched him as he came in. I'd seen him check the hotel register and exchange a few words with the proprietor. 'How long do you plan to stay?'

'About a week. I go back to work next Monday.' I'd booked the room for seven days. He knew that. 'I'm from Berlin,' I said obsequiously. 'Sometimes I feel I must get away for a few days.'

He grunted.

I showed him my papers. I was described as a German citizen, resident in Berlin, and working as a foreman in a British army stores depot. He stood for a long time with the papers in his hand, looking from the documentation to me and then back again. I had the impression he did not entirely believe my cover story, but plenty of West Berliners came down the autobahn and took their vacations here on the easternmost edge of West Germany. And if he contay the army my cover story would hold up.

'Why here?' said the border guard.

'Why not here?' I countered. He looked out of the window. The rain continued relentlessly. Across the road, workmen were demolishing a very old half-timbered building. They continued working despite the rain. As I watched, a wall fell with a crash of breaking laths and plaster and a shower of rubble. The bleached plaster went dark with raindrops and the cloud of dust that rolled out of the wreckage was quickly subdued. The fallen wall revealed open fields beyond the village, and a shiny strip that was a glimpse of the wide waters of the great Elbe river that divided East from West. The Elbe had always been a barrier; it had even halted Charlemagne. Throughout history it had divided the land: Lombard from Slav, Frank from Avar, Christian from Barbarian, Catholic from Protestant, and now communist from capitalist. 'It's better than over there,' I said.

'Anywhere is better than over there,' said the guard with ill-humour, as if I'd avoided his question. Beyond him I saw the proprietor's son Konrad come into the breakfast room. Konrad was a gangling eighteen-year-old in blue jeans and a cowboy shirt with fringes. He was unshaven but I had yet to decide whether this was a deliberate attempt to grow a beard or a part of the casual indifference he seemed to show for all aspects of his morning ablutions. He began setting the tables for lunch. On each he put cutlery and wineglasses, linen napkins and cruet, and finally a large blue faience pot of special mustard for which the Golden Bear was locally famous. Despite the care and attention he gave to his task I had no doubt that he'd come into the room to eavesdrop.

'I walk,' I said. 'The doctor said I must walk. It's for my health. Even in the rain I walk every day.'

'So I heard,' said the guard. He dropped my identity papers on to the red-checked tablecloth alongside the basket containing breakfast rolls. 'Make sure you don't walk in the wrong direction. Do you know what's over there?'

He was looking out of the window. One hand was in his pocket, the thumb of the other hooked into his belt. He looked angry. Perhaps it was my Berlin accent that annoyed him. He sounded like a local; perhaps he didn't like visitors from the big city, and whatever Berliners said it could sound sarcastic to a critic's ear. 'Not exactly,' I said. Under the circumstances it seemed advisable to be unacquainted with what was 'over there'.

The white-faced Oberstabsmeister took a deep breath. 'Starting from the other side you first come to the armed guards of the Sperrzone. People need a special pass to get into that forbidden zone, a is a five-kilometre-wide strip of ground, cleared of trees and ashes, so that the guards can see everything from their towers. The fields there can only be worked during daylight and under the supervision of the guards. Then comes a five-hundred-metre-deep Schutzstreifen. The fence there is three metres high and made of sharp expanded metal. The tiny holes are made so that you can't get a hold on it, and if your fingertips are so small that they can go into the gaps – a woman's or a child's fingers, for instance – the metal edge will cut through the finger like a knife. That marks the beginning of the "security zone" with dog patrols – free running dogs sometimes – and searchlights and minefields. Then another fence, slightly higher.'

He pursed his lips and closed his eyes as if remembering the details from a picture or a diagram. He was speaking as a child recites a difficult poem, prompted by some system of his own rather than because he really understood the meaning of what he said. But for me his words conjured a vivid memory. I'd crossed such a border zone one night in 1978. The man with me had been killed. Poor Max, a good friend. He'd screamed very loudly so that I thought they'd be sure to find us but the guards were too frightened to come into the minefield and Max took out the searchlight with a lucky shot from his pistol. It was the last thing he did; the flashes from the gun showed them where he was. Every damn gun they had was fired at him. I'd arrived safely but so shattered that they took me off the field list and I'd been a desk man ever since. And now, listening to the guard, I did it all again. My face felt hot and there was sweat on my hands.

The guard continued. 'Then a ditch with concrete sides that would stop a tank. Then barbed wire eight metres deep. Then the Selbstschtissgeräte which are devices that fire small sharp pieces of metal and are triggered by anyone going near them. Then there is a road for patrol cars that go up and down all the time. And on each side of that roadway there's a carefully raked strip that would show a footmark if anyone crossed it. Only then do you get to the third and final strip: the Kontrollstreifen with another two fences, very deep barbed wire, more minefields and observation towers manned by machine-gunners. I don't know why they bother to man the towers in the Kontrollstreifen; as far as we know, no escaper along this section has ever got within a hundred metres of it.' He gave a grim little chuckle.