Mount Everest is the Earth's highest mountain

Mount Everest is the Earth's highest mountain, with a peak at 8,848 metres (29,029 ft) above sea level and the 5th tallest mountain measured from the centre of the Earth. It is located in the Mahalangur section of the Himalayas. The international border between China and Nepal runs across the precise summit point. Its massif includes neighboring peaks Lhotse, 8,516 m (27,940 ft); Nuptse, 7,855 m (25,771 ft) and Changtse, 7,580 m (24,870 ft).

In 1856, the Great Trigonometric Survey of British India established the first published height of Everest, then known as Peak XV, at 29,002 ft (8,840 m). In 1865, Everest was given its official English name by the Royal Geographical Society upon a recommendation by Andrew Waugh, the British Surveyor General of India. Waugh named the mountain after his predecessor in the post, Sir George Everest. Although Tibetans had called Everest "Chomolungma" for centuries, Waugh was unaware of this because Tibet and Nepal were closed to foreigners.

Mount Everest attracts many highly experienced mountaineers as well as capable climbers willing to hire professional guides. While not posing substantial technical climbing challenges on the standard route, Everest presents dangers such as altitude sickness, weather and wind.

Discovery

In 1802, the British began the Great Trigonometric Survey of India to determine the location and names of the world's highest mountains. Starting in southern India, the survey teams moved northward using giant theodolites, each weighing 500 kg (1,100 lb) and requiring 12 men to carry, to measure heights as accurately as possible. They reached the Himalayan foothills by the 1830s, but Nepal was unwilling to allow the British to enter the country because of suspicions of political aggression and possible annexation. Several requests by the surveyors to enter Nepal were turned down.

The British were forced to continue their observations from Terai, a region south of Nepal which is parallel to the Himalayas. Conditions in Terai were difficult because of torrential rains and malaria. Three survey officers died from malaria while two others had to retire due to failing health.

Nonetheless, in 1847, the British continued the Great Trigonometric survey and began detailed observations of the Himalayan peaks from observation stations up to 240 km (150 mi) away. Weather restricted work to the last three months of the year. In November 1847, Andrew Waugh, the British Surveyor General of India made several observations from the Sawajpore station located in the eastern end of the Himalayas. Kangchenjunga was then considered the highest peak in the world, and with interest he noted a peak beyond it, about 230 km (140 mi) away. John Armstrong, one of Waugh's officials, also saw the peak from a location farther west and called it peak "b". Waugh would later write that the observations indicated that peak "b" was higher than Kangchenjunga, but given the great distance of the observations, closer observations were required for verification. The following year, Waugh sent a survey official back to Terai to make closer observations of peak "b", but clouds thwarted all attempts.

In 1849, Waugh dispatched James Nicolson to the area, who made two observations from Jirol, 190 km (120 mi) away. Nicolson then took the largest theodolite and headed east, obtaining over 30 observations from five different locations, with the closest being 174 km (108 mi) from the peak.

Nicolson retreated to Patna on the Ganges to perform the necessary calculations based on his observations. His raw data gave an average height of 9,200 m (30,200 ft) for peak "b", but this did not consider light refraction, which distorts heights. However, the number clearly indicated, that peak "b" was higher than Kangchenjunga. Then, Nicolson contracted malaria and was forced to return home without finishing his calculations. Michael Hennessy, one of Waugh's assistants, had begun designating peaks based on roman numerals, with Kangchenjunga named Peak IX, while peak "b" now became known as Peak XV.

In 1852, stationed at the survey headquarters in Dehradun, Radhanath Sikdar, an Indian mathematician and surveyor from Bengal, was the first to identify Everest as the world's highest peak, using trigonometric calculations based on Nicolson's measurements. An official announcement that Peak XV was the highest was delayed for several years as the calculations were repeatedly verified. Waugh began work on Nicolson's data in 1854, and along with his staff spent almost two years working on the calculations, having to deal with the problems of light refraction, barometric pressure, and temperature over the vast distances of the observations. Finally, in March 1856 he announced his findings in a letter to his deputy in Calcutta. Kangchenjunga was declared to be 28,156 ft (8,582 m), while Peak XV was given the height of 29,002 ft (8,840 m). Waugh concluded that Peak XV was "most probably the highest in the world". Peak XV (measured in feet) was calculated to be exactly 29,000 ft (8,839.2 m) high, but was publicly declared to be 29,002 ft (8,839.8 m) in order to avoid the impression that an exact height of 29,000 feet (8,839.2 m) was nothing more than a rounded estimate

First successful ascent by Tenzing and Hillary

In 1953, a ninth British expedition, led by John Hunt, returned to Nepal. Hunt selected two climbing

pairs to attempt to reach the summit. The first pair (Tom Bourdillon and Charles Evans) came within 100 m (330 ft) of the summit on 26 May 1953, but turned back after running into oxygen problems. As planned, their work in route finding and breaking trail and their caches of extra oxygen were of great aid to the following pair. Two days later, the expedition made its second and final assault on the summit with its second climbing pair, the New Zealander Edmund Hillary and Tenzing Norgay, a Nepali sherpa climber from Darjeeling, India. They reached the summit at 11:30 am local time on 29 May 1953 via the South Col Route. At the time, both acknowledged it as a team effort by the whole expedition, but Tenzing revealed a few years later that Hillary had put his foot on the summit first. They paused at the summit to take photographs and buried a few sweets and a small cross in the snow before descending.

News of the expedition's success reached London on the morning of Queen Elizabeth II's coronation, 2 June. Returning to Kathmandu a few days later, Hunt (a Briton) and Hillary (a New Zealander) discovered that they had been promptly knighted in the Order of the British Empire, a KBE, for the ascent. Tenzing, a Nepali sherpa who was a citizen of India, was granted the George Medal by the UK. Hunt was ultimately made a life peer in Britain, while Hillary became a founding member of the Order of New Zealand. Hillary and Tenzing are also nationally recognized in Nepal, where annual ceremonies in schools and offices celebrate their accomplishment.