The fourth-highest mountain in the world, Mount Lhotse, rises 8,516 meters (27,940 ft) above sea level.  It is situated on the boundary between Tibet and Nepal in the Himalayas.  Just south of Mount Everest lies its long east-west crest, and the South Col, a vertical ridge that never descends below 8,000m, links the two mountains' summits.  Lhotse Main, 8512m, Lhotse Shar, 838m, and Lhotse Middle or East, 8413m, are the three peaks of Lhotse.  The West Face of Lhotse is marked by a deep scar, an icy gully called the Lhotse Couloir. The couloir is the most important challenge for the Lhotse climb since its climbing conditions are influenced by seasonal snowfall and weather.

Ernst Reiss and Fritz Luchsinger led a Swiss team that made the first ascent of Mount Lhotse on May 18, 1956.  They took the West Ridge, the same path taken by the 1953 first ascent of Mount Everest, to reach the summit.  There have been numerous successful ascents of Mount Lhotse since the initial ascent, with most climbers taking the South Col route—the same route used to ascend Mount Everest.  Only a small number of people have successfully climbed the south face of Lhotse, which is renowned for being steep and technically difficult.