Mr Bonington co-led the Verifone British Indian Kinnaur expedition, which returned recently after becoming the first to visit the upper reaches of the Tirung Gad, in the Kinnaur range.
'It's immensely satisfying to stand where no one has stood before,' Mr Bonington said. 'Everything falls away and I get a wonderful sense of relief and pleasure.'
The 12-man expedition was also one of the first to 'go green', ensuring there was no litter or equipment left behind in an area increasingly spoilt by the growing numbers of tourists, trekkers, mountaineers and soldiers.
On the Kinnaur expedition, all litter was carried off the mountains, burnt, or buried deep enough to prevent animals from digging it up. The only trace left behind by the 12 climbers was a rope which could not be detatched.
Point 6,553m, a peak the group climbed on 20 June, was named Rangrig Rang (God-made), after the Buddhist monastery at its foot.