K2

K2 is the second-highest mountain on Earth at 8,611 metres, just 238 m shorter than Mount Everest. It is also widely regarded as the hardest of the world's 8,000-metre peaks to climb. Mountaineers call it the Savage Mountain: for every four people who reach the summit, one dies trying. K2 sits in the Karakoram range on the border between Pakistan and China.

• Height8,611 mJust 238 m shorter than Everest
• CountryPakistan and ChinaOn the border between the two
• RangeKarakoramPart of the wider Himalayan system
• Death rateapprox. 25%About 1 in 4 climbers who try the summit die
• First climbed1954By an Italian expedition
• NicknameSavage MountainFor its extreme difficulty

How does K2 compare?

Height (metres)

Everest8,849

K28,611

Kangch.8,586

Aconc.6,961

K2 is only 238 metres shorter than Everest. Both are above the "death zone" of 8,000 metres, where there is barely enough oxygen for humans to survive.

What is K2?

K2 is a steep, pyramid-shaped mountain in the Karakoram range, which is part of the wider mountain system that includes the Himalayas. It sits on the border between Pakistan (where it is called Chhogori, "King of Mountains") and the Xinjiang region of China. K2 has no easy route to the top: every face of the mountain involves steep technical climbing on rock and ice, often through avalanche-prone terrain.

The strange name

K2 has the strangest name of any famous mountain. It does not mean anything in any language: it is just a survey label. In 1856 a British surveyor named Thomas Montgomerie was mapping the Karakoram range from a distance. He labelled the peaks in order: K1, K2, K3, K4, K5. Most of those peaks already had local names; the "K" labels were soon replaced. But K2 was so remote that nobody on the local side knew it well, and the survey label stuck. Pakistan calls it Chhogori; China sometimes calls it Qogir Feng. Around the world, it is just K2.

Fact The death rate on K2 is around 25%, meaning about one in four people who try to climb it die in the attempt. The death rate on Everest is closer to 4%. K2 is much more technically difficult, has worse weather, and has no easy escape route.

Why it is so hard

K2 is harder to climb than Everest for several reasons:

• It is steeper. The face of the mountain rises almost vertically in some sections, requiring proper technical climbing rather than the long walks of the Everest South Col route.
• The weather is worse. K2 sits further from the equator than Everest and is hit by storms more often. Summit attempts often have to wait for narrow weather windows of just a few days a year.
• The "Bottleneck" is a narrow couloir near the summit that runs underneath a massive overhanging block of ice (a serac). Climbers have to pass beneath the serac. If it falls, anyone underneath dies.
• There is no easy descent. If something goes wrong high on K2, helicopters cannot rescue you and the route down is just as dangerous as the route up.

Famous climbs and disasters

The first successful climb of K2 was on 31 July 1954 by Italians Lino Lacedelli and Achille Compagnoni. The expedition was controversial: their teammate Walter Bonatti and Hunza porter Amir Mehdi were left out overnight at 8,100 metres without a tent, in the most dangerous bivouac in mountaineering history. They both survived, but the dispute over the expedition leadership lasted for decades.

The worst disaster on K2 was in 2008, when 11 climbers died in a single 27-hour period after the Bottleneck serac collapsed and swept away the fixed ropes that climbers needed for descent.

Did you know? The first winter ascent of K2 was not made until January 2021, by a team of ten Nepali climbers led by Nirmal Purja and Mingma G. K2 was the last of the world's 14 eight-thousand-metre peaks to be climbed in winter, after over 30 years of attempts.

Deeper dive: the Karakoram, the Bottleneck and the eight-thousanders

The Karakoram is a 500 km mountain range that runs roughly east-west along the border between Pakistan, India, China and Afghanistan. It contains four of the world's 14 eight-thousanders (K2, Gasherbrum I, Broad Peak and Gasherbrum II), plus several thousand other peaks of varying heights. The range was formed by the same tectonic collision between India and Asia that built the Himalayas, but the Karakoram has steeper, more glaciated terrain. The Karakoram contains the highest concentration of high peaks anywhere in the world: more than 60 peaks are above 7,000 metres in just a 50 km cluster around K2.

The Bottleneck is a couloir (a narrow steep gully) at around 8,200 metres on K2's standard Abruzzi Spur route. Above the Bottleneck hangs a massive ice cliff (a serac) the size of a multi-storey building. The Bottleneck is the only practical route past this overhanging mass. The serac periodically collapses, sending huge falls of ice down through the Bottleneck. The 2008 K2 disaster was triggered by exactly this kind of collapse, which swept away the fixed ropes needed for the descent. Climbers above the serac on summit day are often forced to make a dangerous unroped descent through avalanche debris.

K2 is one of the 14 mountains over 8,000 metres above sea level, the so-called "eight-thousanders". All are in Asia: ten in the Himalayas, four in the Karakoram. The first eight-thousander to be climbed was Annapurna I in 1950 (by a French expedition). The last was Shisha Pangma in 1964. Climbing all 14 is one of the great achievements in mountaineering and was first accomplished by Reinhold Messner of Italy in 1986. By 2024 around 50 people had completed all 14. Nirmal Purja became famous for climbing all 14 in just six months and six days in 2019, and for leading the first winter ascent of K2 in 2021.

For the only taller mountain on Earth, see Mount Everest. The range it sits in is part of the wider Himalayas.