Facts About Mount Everest: Height, History and Conditions

Mount Everest, on the border between Nepal and the Tibet Autonomous Region of China, is the highest mountain above sea level. Its summit has become a symbol of human endurance, and the facts about it are as striking as the legends.

Key takeaways

• Everest's official height is 8,848.86 metres, agreed by Nepal and China in 2020.
• It is still being pushed up slowly by tectonic forces.
• Edmund Hillary and Tenzing Norgay made the first confirmed ascent in 1953.
• Above about 8,000 metres is called the "death zone" because oxygen is very low.
• Many climbers use supplemental oxygen, and conditions are dangerous.

Height and names

For decades, measurements differed slightly. In December 2020, Nepal and China jointly announced a new official height of 8,848.86 metres, or about 29,032 feet. The mountain is known as Sagarmatha in Nepali and Chomolungma in Tibetan. The English name honours Sir George Everest, a British surveyor general of India, although he did not choose it and reportedly objected to it.

How it formed

Everest is part of the Himalayas, created by the collision between the Indian and Eurasian tectonic plates, which began tens of millions of years ago and continues today. The summit is made of marine limestone containing fossils, a sign that the rocks formed under an ancient sea. The mountain is thought to rise by a few millimetres a year, though erosion and earthquakes also affect it.

The tallest, but not in every way

Everest has the highest summit above sea level. If measured from base to peak, Mauna Kea in Hawaii is taller, since most of it lies under the ocean. And if measured from the centre of the Earth, the peak of Chimborazo in Ecuador is farthest, because the Earth bulges at the equator.

The first ascent

On 29 May 1953, New Zealander Edmund Hillary and Sherpa Tenzing Norgay reached the summit as part of a British expedition. Earlier attempts included those of George Mallory and Andrew Irvine in 1924, who disappeared high on the mountain. Whether they reached the top remains unknown.

The death zone

Atmospheric pressure at the summit is about one third of that at sea level, so each breath contains much less oxygen. Above roughly 8,000 metres, the body cannot acclimatise fully, and it deteriorates. Most climbers use bottled oxygen near the top. Dangers include altitude sickness, frostbite, avalanches, falls and exhaustion, and temperatures can drop far below freezing with violent winds. Climbers spend weeks acclimatising on the mountain before a summit attempt.

The Sherpa people

Sherpas, an ethnic group from the Himalayan region, play a central role in expeditions, fixing ropes, carrying loads and guiding. They also face the highest risks. Many have summited the mountain multiple times, and there is ongoing discussion about safety, pay and insurance.

Crowds and clean-up

Popularity has led to crowding on the summit routes in good-weather windows and to problems with waste. Authorities and local organisations run clean-up campaigns, and rules now require climbers to bring their waste down. Climbing seasons are generally in spring, before the monsoon.

Routes and the climbing season

There are two main routes. The southeast ridge route starts in Nepal, passing through the Khumbu Icefall, a moving maze of crevasses and towers of ice, then up the Western Cwm to the South Col and the summit ridge. The northeast ridge route starts in Tibet and is technically different, with notable obstacles such as the Second Step. Climbers move up and down between camps in a series of rotations to acclimatise, spending weeks at altitude before a summit push. The window of good weather in May, before the summer monsoon, is short, which is why many climbers set out on the same few days.

Risks and deaths

Everest is dangerous. Hundreds of climbers have died on the mountain since the first attempts, from avalanches, falls, altitude sickness, exposure and exhaustion. In 2014, an avalanche in the Khumbu Icefall killed sixteen Nepali guides, and in 2015 an earthquake caused avalanches that killed people at base camp. The 2023 season was one of the deadliest on record. Rescues at extreme altitude are difficult because helicopters cannot easily operate there and carrying a person down takes many people. Crowds, inexperience and delays near the summit add to the risk.

Sherpa expertise and the Ice Doctors

Sherpas and other mountain workers carry loads, set up camps, rescue clients and fix ropes. A team known as the Icefall Doctors prepares the route through the Khumbu Icefall each season, laying ladders and ropes. Many Sherpa climbers have summited the mountain more times than any foreign climber, and Kami Rita Sherpa has reached the top more than twenty-five times. Their work is risky and often poorly insured, and there are continuing efforts to improve pay, insurance and training.

Climate change and the Himalaya

The Himalayan glaciers are changing. Studies show that many are losing ice, including the Khumbu Glacier near Everest base camp, and meltwater lakes are expanding. Retreating ice has exposed bodies and equipment left by earlier expeditions. Changes in snow and ice also alter the route conditions, and some scientists worry that more unstable ice makes the climb riskier. The region provides water for hundreds of millions of people downstream, so the changes matter well beyond mountaineering.

Rubbish and clean-up

Decades of expeditions left oxygen bottles, tents and human waste on the mountain. Clean-up campaigns have removed large amounts, and rules now require climbers to carry their waste back to base camp, where it is taken away. Some expeditions pay a deposit that is refunded if they return with a set amount of rubbish. Sustainable practices remain a challenge in such a harsh, remote environment.

Frequently asked questions

Is Everest the hardest mountain?

It is the highest, but other peaks, such as K2, are considered technically harder and more dangerous.

Can you see Everest from space?

Not clearly as a separate feature with the naked eye. Satellites can photograph the region.

Does Everest get taller?

It rises a little each year due to tectonic uplift, and measurements are updated occasionally.

How long does an Everest expedition take?

Most commercial expeditions last six to eight weeks, because climbers need time to acclimatise by going up and down between camps before the summit attempt. The final push from the high camp to the summit and back takes about a day.

How much does it cost to climb Everest?

Costs vary widely. Budget expeditions can cost tens of thousands of dollars, and premium services can exceed one hundred thousand. Costs cover permits, guides, oxygen, equipment, food, camps and insurance, and cutting corners can be dangerous.

Has anyone climbed Everest without bottled oxygen?

Yes. In 1978, Reinhold Messner and Peter Habeler made the first ascent without supplemental oxygen, and Messner later climbed it solo without oxygen in 1980. A small number of climbers have repeated this, but it is extremely demanding.

Sources and further reading

• Mount Everest (Wikipedia)
• Britannica: Mount Everest