This was the valley that I had been interested in all along. So in a scaled-down team of five climbers we set off with minimal supplies and, in good old-fashioned explorer's style, started hacking our way through bamboo and vines. The setting was quite surreal, because most of the time the place was under cloud cover. We occasionally got a glimpse of the valley below us and we did have sketchy maps, but basically couldn't see where we were heading.
To get on to the mountain we had to weave our way in an improbable line through chaotic ice fields and crevices. It took us two rather tiring days to make final camp, then four of us went on ahead to the summit while Chris Bonnington stayed behind. We set off at three in the morning and faced some fairly arduous climbing. Consequently we did not make the summit until three in the afternoon.
Bearing in mind that we had a bus to catch in three days, we decided to come straight down. The four of us made a very slow and painstaking descent and quite quickly darkness fell. At about 2am Chris, who was looking out for us at top camp, said that he spotted the lights from our head torches approaching. He followed our path down the mountain when suddenly he saw one of the lights plummet about 300 feet and heard the sound of metal on rock and then the soft thudding of a body hitting the mountain. I experienced every climber's nightmare - the pin had come out of my anchor and I had fallen.
I don't remember much except the strangely slow realisation that I was going to die. A sharp stab of fear and then, oddly, a feeling of regret. And then the appalling, battering violence of hitting the rock and wondering how much longer it could possibly last.
I don't know how much later I came to, but I remember being very surprised I did so at all. I was at the top of a large ice field and should have fallen another 1,000 feet, but my ropes had attached themselves to something.
For a long time I just lay there and then started to inspect the parts, to see what the damage was. I called out feebly to the others and eventually made contact. I think they were quite surprised to find that the weight on the end of the ropes was not a stiff. I shouted melodramatically that I had severed an artery, as there was rather a mess of blood on the snow, but miraculously I had just broken my legs.
I'm not sure how long it took the others to get to me but it took a long, hard day's work to lower me down the ice field. We camped at the bottom for a further four days while Bonnington made it down to send up an Indian air force helicopter, which made an incredibly courageous landing in order to get me out.
In the meantime I had remained strangely blase at the possibility of getting gangrene. I just thought, "I'll get through this." But if it hadn't been for the helicopter I probably wouldn't have.
I still go on expeditions but I am more aware of my own mortality. I am also profoundly aware of the strength, courage and loyalty that human beings can show one another. I think that climbers are people who have to accept their own mortality. And that is something that is far less frightening for me now.
Stephen Venables's book about his experiences in the Himalayas, `A Slender Thread', will be published 6 January 2000 (Hutchinson, pounds 17.99).