Spanish climber and mountain runner Kilian Jornet planned to attempt a record-breaking speed ascent and descent of the north side of Everest during the monsoon period. He was accompanied to Tibet by fellow Spaniard Jordi Tosas and French filmmakers and alpinists Vivian Bruchez (one of France's best skiers of steep terrain) and Sébastien Montaz-Rosset.
After acclimatizing in Langtang, the four arrived at Rongbuk on August 19, and over the next couple of days they climbed several summits up to 6,500m. The team then set advanced base camp at about 6,050m, their yaks unable to reach the usual site at 6,500m due to ice and difficult river crossings. On the 27th, Tosas summited Changtse (7,519m) via the east ridge in a round trip of nine hours.
On August 31, Jornet, Montaz-Rosset, and Tosas tried a new line up Everest on the far right side of the north-northeast face, not far from the north ridge. Their planned ascent was the shorter couloir to the right of the line followed during the February 1988 attempt on the face by Japanese Tsuneo Hasegawa and Kiyotaka Hoshino, which ended at 7,700m (the Japanese followed a more significant couloir that eventually was climbed, in 1996, by Russians). The goal was to climb the shorter couloir until it meets the north ridge at around 7,900m, from where they hoped to follow the Messner traverse and Norton Couloir to the summit.
Leaving the 6,100m camp on Everest's normal route, the three climbers crossed the bergschrund at 6,500m and climbed mainly snow (50°) with easy mixed sections to around 7,600m, where bad weather and snowfall made conditions too avalanche-prone. From there they traversed right to the north ridge, reaching it at approximately 7,680m, and descended via the North Col.
The round trip from camp was 15 hours, at an average rate of vertical gain, from bergschrund to 7,600m, of 180m/hour. They climbed unroped throughout and had no camps on the mountain.
On September 11, Montaz-Rosset climbed Changzheng Tse (6,916m, on the ridge north of Changtse) via the southeast face, then skied down, completing a round trip of about four and a half hours. The same day, Jornet climbed Changtse via the northeast slope to gain the east ridge at 7,200m and then followed this to the summit. (His line on the northeast face was a little left of the 1986 Japanese route.) He was back in camp 11 hours 45 minutes after leaving it.
On the following day Jornet made a fast push, solo, to 7,950m on the north ridge of Everest, ascending from the North Col at more than 200m/hour. The day after, Bruchez, Jornet, and Montaz-Rosset attempted Jianbing Tse (6,853m, just south of Changzheng Tse) by the 400m northeast face, with Jornet reaching the summit (average ascent rate of over 350m/hour) and the two other climbers stopping below.
Information provided by Jordi Tosas, Spain, and Rodolphe Popier, The Himalayan Database, France