Time line for Cho Oyu in Nepal.

1952 First reconnaissance of north-west face by Edmund Hillary and party.[1]
1954 First ascent by Austrians Joseph Jöchler and Herbert Tichy, and Pasang Dawa Lama (Nepal)[1]
1958 Second ascent of the peak, by an Indian expedition. Sherpa Pasang Dawa Lama reached the peak for the second time. First death on Cho Oyu.[1]
1959 Four members killed in an avalanche during a failed international women's expedition.[1]
1964 Controversial third ascent by a German expedition as there is no proof of reaching the summit. Two mountaineers die of exhaustion in camp 4 at 7,600m (24,935ft).[1]
1978 Edi Koblmüller and Alois Furtner of Austria summit via the extremely difficult southeast face.[1]
1983 Reinhold Messner succeeds on his fourth attempt,[1] with Hans Kammerlander and Michael Dacher.
1984 Dina Štěrbová, Věra Komárková. First women expedition.
1985 On February 12, Maciej Berbeka and Maciej Pawlikowski make the first winter ascent (repeated three days later by Andrzej Heinrich and Jerzy Kukuczka).
1994 First solo ascent via the South West face by Yasushi Yamanoi.
2009 Clifton Maloney, husband of United States Congresswoman Carolyn Maloney, dies after climbing the mountain.