Reinhold Messner: I started in darkness — but only the first night — because from the base camp onwards, I knew more or less the terrain. So I could start at midnight, and I had a headlamp, and I could orientate. But higher up, where I did not go before, I went only when the daylight was coming. I was melting snow in the tent. The most important thing up there is that we are drinking because we lose a lot of humidity and water with our very difficult, very strong breath. We are breathing like dogs up there, running dogs. We are hyperventilating. You have to do it because there’s less oxygen.

In reality, the pressure in the air is much less than at home. And on the Everest, this is the limit people can stay on. And I could not take oxygen bottles. I would never be able to carry them by myself. You have to know that in the ‘70s, the oxygen equipment for one man on Everest had the weight of 50 kilos.

So they needed a lot of helpers to bring all this stuff up there. And the first expeditions, when the British and Americans went — and also the Indians, in the ‘50s and the ‘60s, went to Mount Everest — they needed hundreds of porters. They needed tons and tons of materials because also, for the porters which you use, and they help you higher up, you need logistics. You need tents, and you need food, and you need cookers, and so on. And if you go alone, you need only the minimum of necessity, but you have to learn to handle it. And the problem is not a technical one. The north side of Mount Everest is not difficult for a good climber. You can fall also there, but only if you are really stupid, you can fall there.