The mountain was first climbed on October 19, 1954, via the north-west ridge by Herbert Tichy, Joseph Jöchler and Sherpa Pasang Dawa Lama of an Austrian expedition. Cho Oyu was the fifth 8000 metre peak to be climbed, after Annapurna in June 1950, Mount Everest in May 1953, Nanga Parbat in July 1953 and K2 in July 1954. Until the ascent of Mount Everest by Reinhold Messner and Peter Habeler in 1978, this was the highest peak climbed without supplemental oxygen.