A lot of people think they know what happened, but even I don’t know exactly. My brother Günther and I had summited Nanga Parbat and we were elated. We’d taken off our gloves to shake hands, which was foolish — I lost several fingertips to frostbite afterwards — but it was what we always did when we reached a summit. We’d never been on top of an 8,000-metre mountain before.

On the descent, Günther lagged behind, but that was nothing unusual. It was not a question of ability, just that from childhood I’d always been stronger than him, though we had always been a perfect team. We had a high bivouac [overnight camp]. It was very dangerous where we were; we had called to other members of the team for help, but they didn’t hear us. We talked about coming off and I decided the best way down was via the Diamir Face — less steep than our way up. I had a feeling the snow would be good, so we would be quicker — and quicker means less dangerous. So I decided to go ahead and check first, then for my brother to follow.

At first, as I waited for him to catch up, I didn’t have a bad feeling. But then I began to wonder where he was. I was thinking perhaps he had tried to get down on a different line through the glacier. I moved down to meet him, but he didn’t appear there either. I decided to go back up to look for him, though I had to wait a long time for the energy: at that altitude, going upwards is much harder than going down. I slowly made my way back towards the last place I had seen Günther. Then I stumbled on the debris from an avalanche, a jumble of lumps of ice, some as big as cupboards. I could not believe that Günther might be buried there, might be dead. I walked around the glacier in circles, like a madman.

I’ve had 35 years of going over this. He was behind; I was in front, because I was looking for the route. An avalanche could have come to me in front, missing him out. I was lucky and he was unlucky, though you could say different, because my life has not been easy since. But if he’d had the chance to survive, to be the one who lived, then he would have had to live with this tragedy. It’s very simple.

My mother and father heard the news before I got back. The police had been round to our home. I returned 10 days later. Until then my mother still had some hope. It was very difficult for her —Günther had died somewhere at the end of the world and she had nothing of him.

In 2000 I was on Nanga Parbat following the line Albert Mummery took when he died there in 1895. He was one of the most prolific climbers in the world. We found this bone. It seemed too long to be Günther’s, and I thought it might belong to Mummery or to a Pakistani who died in the same place. But I took it home and doctors took saliva swabs from one of my brothers and myself to get a genetic code. This showed a large probability that the bone was Günther’s, though they could not guarantee it. I thought at that point it was his, but we had to keep an open mind. After that I went to Pakistan and asked local people to search in the same area every year in summer when the snow had melted.

In July 2005 I had a call from a man working in Pakistan for the foundation I set up, which builds schools in remote mountain areas. He told me local guides had found human remains near where I believed my brother’s body might be. They had found more or less the whole body — by which I mean the bones, which had travelled about 3½ kilometres down the glacier. For me there had only ever been two possibilities: my brother had either fallen into a crevasse or been killed by an avalanche. When his bones were found, I knew it was an avalanche.

A month later we found many more things in the ice. There were clothes and a boot which I recognised as Günther’s.

I called my brother Hubert and asked him to speak to the rest of my brothers and my sister to decide what we should do. It was agreed that I should burn our brother’s remains on the mountain, in the Tibetan way, and later we would all have another ceremony. And so my brother was given a Tibetan cremation, with some Christian prayers, and then we built a memorial out of stones.

I flew home with Günther’s boot and bone samples for DNA, which showed the bone was 17.8m times more likely to be Günther’s than not. At last I felt as if I could lay my brother to rest and put aside 35 years of accusations.

The other climbers on that expedition never became as successful as me. They became famous by accusing me of neglecting my brother. Who could think I would abandon him up there? When my son was small, he saw something on TV and asked his mother if I would go to prison for murdering my brother.

They had no right to do that. But now Günther and this story are at rest.

Interview: Alice Douglas.

Portrait: Steve Peake

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