Timeline of Mount Everest expeditions


is the world's highest mountain, with a peak at above sea level. It is situated in the Himalayan range of Solukhumbu district, Nepal.

Timeline

1921: Reconnaissance expedition

The first British expedition—organized and financed by the newly formed Mount Everest Committee—came under the leadership of Colonel Charles Howard-Bury, with Harold Raeburn as mountaineering leader, and included George Mallory, Guy Bullock, and Edward Oliver Wheeler. It was primarily for mapping and reconnaissance to discover whether a route to the summit could be found from the north side. As Raeburn's health broke down, Mallory assumed responsibility for most of the exploration to the north and east of the mountain. He wrote to his wife: "We are about to walk off the map..." After five months of arduous climbing around the base of the mountain, Wheeler explored the hidden East Rongbuk Glacier and its route to the base of the North Col. On September 23, Mallory, Bullock, and Wheeler reached the North Col at before being forced back by strong winds. To Mallory's experienced eye, the route up the North ridge intersecting the NE Ridge and from there to the summit looked long, but feasible for a fresher party.

1922: First attempt

The second British expedition, under General Charles Granville Bruce and climbing leader Lt-Col. Edward Lisle Strutt, and containing Mallory, returned for a full-scale attempt on the mountain. On May 21, they climbed to on the North Ridge before retreating. They were the first humans to climb above on a mountain. The scope of this accomplishment is reflected by the fact that there are only 14 mountains on Earth—the eight-thousanders—that reach and exceed 8,000 metres. At that moment, Mallory and Strutt had exceeded the summit of all but five other mountains on the planet.
A day later, George Finch and Geoffrey Bruce climbed up the North Ridge and Face to 8,321 m using oxygen for the first time. They climbed from the North Col to their highest camp at a phenomenal rate of 900 vertical feet per hour, and were the first climbers to sleep using oxygen.

1924: Mallory and Irvine

The third British expedition was led by Brigadier-General Charles Bruce, although becoming indisposed as a result of a flare-up of malaria, he relinquished leadership of the expedition to Lt-Col. Edward Norton, with Mallory promoted to climbing leader. Geoffrey Bruce, Howard Somervell, and John Noel returned from the previous year, along with newcomers Noel Odell and Andrew Irvine.
On June 2, Mallory and Bruce set off from the North Col to make the first summit attempt, but extreme wind and cold, exhaustion, and the refusal of the porters to carry farther led Mallory to abandon the attempt and the next day the party returned to the North Col camp.
On June 4, Norton and Somervell attempted an oxygenless summit in perfect weather; throat trouble forced Somervell to abandon the climb at about while Norton continued on alone, reaching a height of 8,573 m, just 275 m short of the summit. Exhausted, he turned back and rejoined Somervell for the descent.
On June 8, Mallory and Irvine left their high camp at to attempt the summit, using Irvine's modified oxygen apparatus. Odell, climbing in support below, wrote in his diary that at he "saw Mallory & Irvine on the ridge, nearing base of final pyramid" climbing what he thought at the time was the very difficult Second Step at 12:50 pm. It was the last time the two were seen alive; whether either of them reached the summit remains a question still discussed and studied.
Back in England, the climbing establishment pressured Odell to change his view. After about six months he began to equivocate on which Step it was he saw them—from the Second to possibly the First. If the First, they had no chance of having reached the top; if the Second, they would have had about three hours of oxygen each and the summit was at least three hours away. It is conceivable that Mallory might have taken Irvine's remaining oxygen and attempted to reach the summit alone.
One possible scenario is that the two reached the First Step at about 10:30am, and Mallory, seeing the treacherous nature of the traverse to the Second Step, elected to go it alone. He may have reconnoitered the base of the climbing crux and decided it was not for him that day. He returned, picked up Irvine and the two decided to climb the First Step for a look around and to photograph the complex approach to the Second Step. It was perhaps when climbing this small promontory that they were spotted from below by Odell, who assumed that, since they were ascending, they must therefore have been on the Second Step, although it is now difficult to believe that the two would still be climbing from so low down at a time—five hours late—that was considered to be the turn-around hour. Descending from the First Step, the two continued down when, at 2pm, they were hit by a severe snow squall. Roping up, Mallory, leading, may have slipped, pulling himself and Irvine down. The rope must have caught to inflict severe rope-jerk injury around Mallory's waist. Some researchers believe Irvine was able to stay high and struggle along the crest of the Northeast Ridge another 100 yards, only to succumb to cold and possible injuries from the fall. Others believe that the two became separated after the fall by the near white-out conditions of the squall. Based on his final location, it would seem that Mallory had continued straight down in search of his partner, while Irvine, also injured, might have continued diagonally down through the Yellow Band.
In 1979, climber Wang Hongbao of China revealed to the climbing leader of a Japanese expedition that in 1975, while taking a stroll from his bivouac, he had discovered "an English dead" at , roughly below the site of Irvine's ice axe discovered in 1933 near the Northeast Ridge. Wang was killed in an avalanche the next day before he could provide additional details.
In 1999, Conrad Anker of the Mallory and Irvine Research Expedition found Mallory's body in the predicted search area near the old Chinese bivouac. There are opposing views within the mountaineering community as to whether the duo may have reached the summit 29 years before the first documented successful ascent by Sir Edmund Hillary and Tenzing Norgay in 1953. Many theories regarding the success of Mallory and Irvine's summit assault exist.
One theory amongst those supporting a successful summit push has Mallory overcoming the difficulty of the sheer face of the Second Step by standing on Irvine's shoulders. Armed with Irvine's remaining 3/4-full oxygen tank, he could conceivably have reached the summit late in the day, but this would have meant that Irvine would have had to descend by himself. However, rope-jerk injuries around Mallory's waist must mean the two were roped when they fell from below the First Step. Others suggest based on subsequent free climbs that Mallory would have been able to free climb the step. Chinese climber Xu Jing told Eric Simonson and Jochen Hemmleb in 2001 that he recalled spotting a corpse somewhere in the Yellow Band when he climbed Everest in the 1960s. One researcher claimed to have finally spotted Irvine's body using microscopic examination of aerial photographs. This possible discovery set off a new round of search expeditions in 2010 and 2011. Irvine's foot was found in the Central Rongbuk Glacier in 2024.

1933

A major expedition, under the leadership of Hugh Ruttledge, set out to climb with the great expectations that this time they would succeed. Oxygen was taken but not used because of the incorrect but lingering belief that it was of little benefit to a properly acclimated climber. After delays caused by poor weather and illness of team members, a much higher assault camp was placed than in 1924. On the first summit attempt, Lawrence Wager and Percy Wyn-Harris intended to follow the Northeastern ridge, but were unable to regain it, having bypassed the First Step, which they reached at 7:00am. The direct access to the Second Step from the First involves a treacherous traverse. Instead of taking it, they dropped down to follow the lower, easier traverse pioneered by Norton in 1924. Observing the Second Step from below it, Wyn-Harris declared it "unclimbable." Shortly after crossing the Great Couloir, they turned back for poor snow conditions and the lateness of the hour. A subsequent attempt by Eric Shipton and Frank Smythe followed the same route but Smythe, who pressed on alone when Shipton turned back because of illness, got no higher.
Lucy, Lady Houston, a British millionaire former showgirl, funded the Houston Everest Flight of 1933, which saw a formation of airplanes led by the Marquess of Clydesdale fly over the summit in an effort to photograph the unknown terrain.

1934

  • Maurice Wilson, a British eccentric, stated his intention to summit Everest by himself. After only a few flying lessons, Wilson flew illegally from Britain to India, hiking through Darjeeling and into Tibet and with the help of Sherpa guides began his attempt. Wilson was not a climber and had no climbing equipment. He expected to transport himself to the summit with spiritual help and signal the monks at the Rongbuk monastery of his success with a shaving mirror. It is not believed he attained the North Col. Maurice Wilson's body and his diary were found wrapped in a tent in 1935 by another British expedition. Although dumped into a crevasse below the North Col, his body has been rediscovered a number of times, including in 1960 by the Chinese expedition. Unlike Mallory's body, Wilson's has decayed because the temperature at the head of the East Rongbuk Glacier does rise above freezing.

    1935

  • Shipton led a small reconnaissance expedition during the monsoon season in preparation for the following year's expedition. The team climbed smaller peaks in the vicinity of Everest, and examined alternative possible routes on the mountain, including the West Ridge, and entry into the Western Cwm via Lho La. Both were dismissed as impractical, though Shipton did decide that an ascent from the Western Cwm would be possible if entry from the Nepalese side could be made. This would be the route by which the mountain would eventually be climbed in 1953. The expedition is also notable as the first visit to Everest for Tenzing Norgay, who was engaged as one of the 'porters'.