Cho Oyu in the context of Tibetans

Mahālangūr Himāl (Nepali: महालङ्गूर हिमाल, Mahālaṅgūra himāla) is a section of the Himalayas in northeast Nepal and south-central Tibet of China extending east from the pass Nangpa La between Rolwaling Himal and Cho Oyu, to the Arun River. It includes Mount Everest, Lhotse, Makalu, and Cho Oyu — four of Earth's six highest peaks. On the Tibetan side it is drained by the Rongbuk and Kangshung Glaciers and on the Nepali side by Barun, Ngojumba and Khumbu Glaciers and others. All are tributaries to the Koshi River via Arun River on the north and east or Dudh Kosi on the south.

Mahalangur Himal can be divided into three subsections:

Tingri County (Tibetan: དིང་རི་རྫོང་།; simplified Chinese: 定日县; traditional Chinese: 定日縣; pinyin: Dìngrì Xiàn) is a county under the administration of the prefecture-level city of Shigatse in the Tibet Autonomous Region of China.

The county comprises the upper valley of the Bum-chu or Arun River, with the valleys of its tributaries, the valleys of the Rongshar Tsangpo and the Lapchi Gang Tsangpo which flow south into Nepal. It is bordered on the south by the main range of the Himalayas, including Mount Everest (Tib. Jomolangma), Makalu and Cho Oyu. The present county administration is located at Shelkar, about 87 km (54 mi) east of Tingri (town).

Sir Edmund Percival Hillary (20 July 1919 – 11 January 2008) was a New Zealand mountaineer, explorer, and philanthropist. On 29 May 1953, Hillary and Sherpa mountaineer Tenzing Norgay became the first climbers confirmed to have reached the summit of Mount Everest. They were part of the ninth British expedition to Everest, led by John Hunt. From 1985 to 1988 he served as New Zealand's High Commissioner to India and Bangladesh and concurrently as Ambassador to Nepal.

Hillary became interested in mountaineering while in secondary school. He made his first major climb in 1939, reaching the summit of Mount Ollivier. He served in the Royal New Zealand Air Force as a navigator during World War II and was wounded in an accident. Prior to the Everest expedition, Hillary had been part of the British reconnaissance expedition to the mountain in 1951 as well as an unsuccessful attempt to climb Cho Oyu in 1952.

Nangpa La (Chinese: 囊帕拉山口 also known as Chinese: 朗喀巴山口) (el. 5,806 m or 19,050 ft) is a high mountain pass crossing the Himalayas and the Nepal-Tibet Autonomous Region border a few kilometres west of Cho Oyu and some 30 km (20 mi) northwest of Mount Everest. A foot-trail over Nangpa La is the traditional trade and pilgrimage route connecting Tibetans and Sherpas of Khumbu and its historical name was Khumbu La. This was the location of the 2006 Nangpa La shootings.

The Ngozumpa glacier, below the sixth highest mountain in the world Cho Oyu in Nepal, at 36 kilometres (22 mi), is the longest glacier in the Himalayas. Ngozumpa Glacier is a large persistent body of ice. It flows slowly due to stresses induced by its weight.