Istor-O-Nal, Northeast Summit, Attempt. Ten members of the Neuchatel Section of the Swiss Alpine Club attempted the unclimbed northeast summit (7276m) of Istor-O-Nal from the north. The only known previous attempt on this mountain was made by a Japanese team in 1977, in which they attained an altitude of 6500 meters. They climbed an easy but very dangerous couloir that leads to a small col between the north ridge and the unnamed 6241-meter peak that stands right in front of Istor-O-Nal’s north side.
Base Camp was established at 4250 meters on July 11 on the South Udren Glacier. This glacier is incorrectly labeled “South Atrak Glacier” on all mountaineering maps, a label initially bestowed by Japanese climbers. Local people corrected us, and we hereby convey the information. Camp I was established on July 13 on the upper section of the glacier, five kilometers southwest of BC, at 4700 meters. CI was used more as an advanced base camp since it was set at the beginning of the mountaineering difficulties. On July 19, member Thierry Bionda broke his heel while walking on the lower glacier and returned to Switzerland five days later. As the couloir climbed in 1977 by the Japanese was seriously threatened by at least ten hanging glaciers, we chose to climb a rocky western spur of the aforementioned unnamed peak. Having placed 1200 meters of fixed ropes on this steep spur, we finally found a flat place on top of the ridge, below the unnamed summit, to establish CII on July 29. From there, we abseiled 70 meters to reach the upper part of the Japanese couloir and eventually reached the small col at 6000 meters. Camp III was established on August 9 at 6300 meters on the north ridge, which leads to Istor-O-Nal’s northeast summit. The lower section of the ridge was the hardest part of the route. This sharp ridge consists of steep rock towers, ice walls, and big snow cornices, so we fixed a further 500 meters of rope. Above CIII the ridge became easier and we established CIV on August 19 at 6800 meters. Fixed ropes between CI and CII were cut by a big stone avalanche that occurred August 18, when four members were at CIII or above. With no more food and equipment supplies from below, they opted for a rapid summit attempt on August 21. From the upper part of the ridge, they crossed a steep slope on the left, below the summit buttress, and climbed a couloir that lies 400 meters below the summit. From there, they climbed the final snow slope, but found it steeper and harder than they had expected. The temperatures were extremely cold, with a recorded temperature of -30°C inside the CIV tent the morning of the final assault. Progress slowed as they belayed almost every pitch. Two members were starting to develop frostbite on their feet when they reached 7170 meters. Though the summit was right before them, it would have taken two more hours to reach it. At 4 p.m. they decided not to venture higher because of the imminent frostbite and started to descend. At 7 p.m., they divided themselves between CIV and CIII. The day after, having no more valuable food, with painful feet, and with time running out, they abandoned the climbing. The team was composed of Simon Perritaz (leader), Jean-Claude Lanz, André Geiser, André Müller, Albertino Santos, and the four summit attempt members, Antoine Brenzikofer, Christian Willard, Jean-Michel Zweiacker, and Yann Smith.
Simon Perritaz, Swiss Alpine Club