Climbing Mount Everest is among the most dangerous pursuits in the world with a fatality rate of 6.5 per cent of climbers who attempt to summit.
To date almost 300 people have died trying to climb the world’s highest mountain, and some 4,500 have summited.
Nevertheless, its status as the world’s highest mountain at 8,848m (29,029ft) means it will always attract climbers irrespective of the risks involved.
Avalanches, cracking ice flows and deadly crevices are just some of the obstacles faced by climbers. The chief impediment, however, is extreme altitude sickness. The “death zone” is above 8,000 metres.
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The lack of oxygen can disorientate the most experienced climbers, and many perish at this point. Moreover, the bodies of many climbers who fall in the upper reaches of the mountain are never recovered because of the logistical difficulties. They are left on the mountain into perpetuity. It is not unknown for climbers to walk past the bodies of their dead comrades.
The window to climb Mount Everest is narrow - usually between May 10th and May 23rd before the monsoon sets in.
Mount Everest has also been prone to multiple disasters. In 1996 eight people died when a huge storm hit the mountain. It was the subject of the bestselling book and film Into Thin Air.
In April 2014, 16 sherpas were killed when an avalanche hit base camp, and this was followed a year later by the deaths of 19 sherpas in another avalanche caused by an earthquake. The climbing season was cancelled for 2015 as a result.
Nevertheless, Mount Everest is far from the deadliest of the “8,000 club” of mountains over 8,000m. Annapurna 1 Main (8,091m, 26,545ft) has a fatality rate of nearly 50 per cent followed by Kangchenjunga (8,586m, 28,169ft) where two Indian climbers died earlier this week. Both summits are in the Himalayas.
In Pakistan, K2, the second-highest mountain in the world, is renowned for its technical difficulties and hazards. It has a fatality rate of 29 per cent. The numbers who have made it to the summit are tiny in comparison with Mount Everest.