The ascent of Nanda Devi necessitated fifty years of arduous exploration in search of a passage into the Sanctuary. The outlet is the Rishi Gorge, a deep, narrow canyon which is very difficult to traverse safely, and is the biggest hindrance to entering the Sanctuary; any other route involves difficult
passes, the lowest of which is . The first recorded attempt to explore the sanctuary was in 1883 by W. W. Graham, who could proceed only up to Rishi Ganga.
Hugh Ruttledge attempted to reach the peak three times in the 1930s and failed each time. In a letter to
The Times he wrote that 'Nanda Devi imposes on her votaries an admission test as yet beyond their skill and endurance', adding that gaining entry to the Nanda Devi Sanctuary alone was more difficult than reaching the
North Pole.In 1934, the British explorers
Eric Shipton and
H. W. Tilman, with three
Sherpa companions,
Angtharkay, Pasang and Kusang, finally
discovered a way through the Rishi Gorge into the Sanctuary. In 1939, the area was declared as a game sanctuary. (on the right), Shot from
Ranikhet,
Almora] When the mountain was later climbed in 1936 by a British-American expedition, it became the
highest peak climbed by man until the
1950 ascent of Annapurna, . (However, higher non-summit elevations had already been reached by the British on
Mount Everest in the 1920s, and it is possible that
George Mallory may have
reached Everest's summit in 1924.) It also involved steeper and more sustained terrain than had been previously attempted at such a high altitude. This device was designed to intercept telemetry signals from missile test launches conducted in the
Xinjiang Province, at a time of relative infancy in
China's missile program. The expedition retreated due to dangerous weather conditions, leaving the device near the summit of Nanda Devi. They returned the next spring to search for the device, which ended without success. She had been suffering from "diarrhea and flare-up of an
inguinal hernia, which had shown up originally on the second day of the approach march", and had been at for nearly five days. In 1980, the
Indian Army Corps of Engineers made an unsuccessful attempt. This was followed in 1981 by another Indian Army expedition of the
Parachute Regiment, which attempted both main and eastern peaks simultaneously. The expedition had placed a memorial to Nanda Devi Unsoeld at the high altitude meadow of Sarson Patal prior to the attempt. The successful attempt lost all its summiteers. In 1993, a 40-member team of the Indian Army from the
Corps of Engineers was given special permission. The aim of the expedition was multifold: to carry out an ecological survey, clean up the refuse left behind by previous expeditions, and scale the summit. The team led by Lt Col V.K. Bhatt included a number of wildlife scientists and ecologists from
Wildlife Institute of India,
Salim Ali Centre for Ornithology and Natural History,
World Wide Fund for Nature and Govind Ballabh Pant Institute for Himalayan Environment and Development amongst others. The expedition carried out a comprehensive ecological survey and removed from the park, by porter and helicopter, over 1,000 kilogrammes of litter. Additionally, five summiteers reached the summit: Amin Naik, Anand Swaroop, G. K. Sharma, Didar Singh and S. P. Bhatt. ==Recent history and conservation==