
Donald Lynn Cash, 55, collapsed after reaching the summit of Everest. Two accompanying sherpa guides helped him to regain consciousness but he later died on the descent

An American climber collapsed on the summit of Everest while taking photos and died hours later on Wednesday - which was one of the busiest days ever on the mountain as huge lines of climbers formed near the summit.

Dedicated amateur Donald Lynn Cash, 55, from Sandy, Utah, collapsed on top of the 29,029-foot (8,848m) peak on Wednesday as he was taking photographs after a 12-hour push from camp.

His death - the fourth on Everest this year - came as more than 200 climbers were heading towards the summit on both sides of Everest Wednesday as the weather cleared.

Many climbers complained of a traffic jam on the mountain on Sunday, which has become notorious for overcrowding, large numbers of unskilled mountaineers and huge piles of rubbish.

Cash was an experienced mountaineer and recently retired software salesman who was attempting to climb the Seven Summits - the highest peak on each continent.

After his collapse, Sherpas were initially able to perform CPR and managed to get him a short way down.

But just a few hours later Cash died from the effects of the altitude near the Hillary Step - a near-vertical rock face on the southeast ridge.

In the so-called death zone on Everest, above 28,000ft, there is not enough oxygen for a human body to survive for long. Climbers who get stuck above 28,000ft are certain to die.

According to mountaineering reporter Alan Arnette, Cash's body is not recoverable - and his friends said 'his final resting place will probably be exactly where he wanted'.

The guides carried Cash to the Hillary Step, Arnette wrote, amidst huge queues on the fixed ropes that line the route from base camp to the summit.

Cash died on one of the busiest days ever on the mountain as huge queues of climbers formed near the summit.

More than 200 people were taking advantage of clear weather to attempt to summit from both Nepal and China, but teams had to line up for hours to reach the top - risking frostbite and altitude sickness.

Massive line: In this picture taken on Sunday May 22, hundreds of mountain climbers line up to stand at the summit of Mount Everest Many teams waited for hours to reach the summit, risking frostbites and altitude sickness

'Our two Sherpas helped him gain consciousness but he died close to the Hilary Step as they were bringing him back,' said Pasang Tenje Sherpa of Pioneer Adventure

Cash, from Sandy, Utah was a mountain enthusiast who was attempting to complete the Seven Summits, the highest peaks on each continent

How does Everest kill people? 'Altitude sickness' refers to the group of potential dangers faced by high altitudes, and is also known as 'mountain sickness'. It is caused by gaining altitude too rapidly, which doesn't allow the body enough time to adjust to reduced oxygen and changes in air pressure, and causes hypobaric hypoxia (a lack of oxygen reaching the tissues of the body). In severe cases, fluid builds up within the lungs, brain or both. Symptoms of the illness include: headaches, lethargy, a lack of coordination, nausea, dizziness, vomiting, and insomnia. (Source: Better Health Victoria) Advertisement

Many climbers complained of a traffic jam on the mountain, which has become notorious for overcrowding, large numbers of unskilled mountaineers and huge piles of rubbish.

According to a post made by Mr Cash made before his made the climb, the Himalayan was the last in a seven-peak challenge he had set himself.

'I am truly blessed to be able to take the next five months off on a sabbatical to finish the last two remaining mountains on my Seven Summits Club dream,' Cash wrote online.

'Mt. Vinson-Masiff in Antarctica Jan 7 to 26, 2019 and then Everest in Nepal April/May 2019.

'I'm excited to look for the next chapter of my career in June when I return. Safely. With all my digits.'

He had previously trekked to the Everest base camp and was a keen adventurer, and had planned to race a sports car across America's salt flats in the summer.

It is the third fatality on Everest this season, after Ravi Thakar from India died last week and Irish mountaineer Seamus Sean Lawless is presumed dead after he slipped and fell close to the summit.

'We don't have the exact number of summits yet, but it has been a very busy day. Teams have complained of having to wait two or more hours to reach the top,' said Gyanendra Shrestha, a government liaison officer stationed at base camp.

Mountaineering in Nepal has become a lucrative business since Edmund Hillary and Tenzing Norgay made the first ascent of Everest in 1953 and more than 4,000 climbers have now reached the top of Everest, according to the authoritative Himalayan Database.

Recent years have seen especially rapid growth, with the mountain opening up to more people as competition between expedition organisers has caused costs to plummet.

But rising numbers mean greater risk - a higher chance of bottlenecks as larger teams lumber their way to the summit, potential shortages of oxygen tanks, and increased risk of frostbite and even death.

A photo of a huge traffic jam below the summit in 2012 prompted calls for better crowd management, and even a cap on the number of permits issued annually.

Nepal currently grants permits to all who apply and are willing to pay $11,000 to scale the 8,848-metre (29,029-foot) peak. This year the government has handed out 378 climbing permits according to the tourism department.

That tops the previous record of 373 in 2017.

Most Everest aspirants will need the help of Nepali guides to reach the summit, meaning about 750 climbers will tread the same path to the top in the coming weeks when the weather is expected to be most favourable.

And at least 140 others are preparing to scale Everest using the northern route from Tibet, according to expedition operators, taking the potential total past the 2018 record of 807 when five people died.

Spring is the busiest time of year on the mountain as the icy winds and bone-chilling temperatures are more forgiving than at other times.

Donald Cash, from Utah, died on Wednesday on Mount Everest, which was the last in a seven-peak challenge he had set himself

Mr Cash (top right) had previously trekked to the mountain's base camp ten years, and had planned to complete Mt Everest as part of a five-peak challenge he had set himself

What is Hillary Step? Hillary Step is a near-vertical rock face located on the southeast ridge of Mount Everest in the Himalayas. It sits 28,839ft (8,790m) above sea level and is named after Sir Edmund Hillary, the New Zealand mountaineer who was the first to ever climb the mountain, along with Tenzing Norgay. The step is the last challenge climbers face before reaching the summit and can prove deadly. Those who try to get up Hillary Step have a danger of falling 10,000ft (3,00m) on their right and 8,000ft (2,400m) on their left. It is believed several people have died trying to get up the steep ridge, with the late Russian Kazachstani climber Anatoli Boukreev finding a body hanging from the ropes at the base of the steps in the 1990s. He wrote about the horrifying ordeal in his book The Climb. It was first reported in 2016 that the April 2015 Nepal earthquake had changed Hillary Step, but there was too much snow to establish to what extent. In May 2017 climbers heading up the mountain, including six-time Everest climber Tim Mosedale, said: 'Hillary Step is no more'. His interpretation has been subject to debate. But climbers in 2018 have backed up his claim. Edmund Hillary's son was asked about the step based on photos taken by climbers and he agreed there had been some change. He also said it looked like 'fresh broken rock'. In later years coming down the step has been done with the assistance of fixed roped, placed there by officials at the beginning of the season. As more and more people have taken up the challenge, queues have been reported and climbers have been made to wait for hours to get down it. Advertisement

Even so the climbing season is short, with ascents expected to wrap up by the end of May or the first week of June.

Ice doctors, the elite Sherpa mountaineers who set the ropes to the summit for hundreds of paying clients to climb, were forced to wait for a favourable weather window to begin their ascent.

Powerful jet streams raging around the top of Everest over the last few weeks had expedition operators worried about the number of summit days, raising the likelihood of many climbers going up at the same time.

Mountaineering blogger Alan Arnette said that problems could arise at the end of the season due to overcrowding when desperate climbers push onward to the summit despite a narrowing weather window.

'Perhaps Nepal should put a limit like China has done or the US Park Service for Denali,' Arnette said.

'But I doubt Nepal ever will do this because there is too much money at stake and they seem unable to refuse business, regardless of the risks,' he said.

Nepal has raked in over $4 million in Everest permit fees alone in 2019, a much-needed source of revenue for the cash-strapped country.

Expedition operator Dawa Steven Sherpa of Asian Trekking conceded that while 'there are some concerns about overcrowding', mountaineering companies have become better at crowd management and are working together to schedule their teams.

Most Everest hopefuls are escorted by a Nepali guide, meaning more than 750 climbers will tread the same path to the top in the coming weeks.

And at least 140 others have been granted permits to scale Everest from the northern flank in Tibet, according to expedition operators. This could take the total past last year's record of 807 people reaching the summit.

Many Himalayan mountains - including Everest - are at peak climbing season, with the window of good weather between late April and the end of May.

At least six other foreign climbers have died on other 8,000-metre Himalayan peaks while two are missing.

The North face of Mt.Everest seen from the Tibet side during sunset in China. Three people have died traversing the mountain this season, including an Indian climber who died last week and an Irish mountaineer who is presumed dead after he slipped and fell close to the summit