Mount Everest, the highest mountain in the world at 29,035 feet (8,850 meters), is also the highest graveyard. Many climbers have died on Mount Everest since 1921 and over 200 of them are still on the mountain. Some are buried in crevasses, some fell down remote parts of the mountain, some are buried in snow and ice and some lie in the open. And some dead climbers sit beside the popular routes up Mount Everest.

Death Rate on Everest is 6.5% of Summit Climbers

There is no firm count of the exact number of climbers that have died on Mount Everest, but as of 2016, about 280 climbers have died, about 6.5 percent of the more than 4,000 climbers who have reached the summit since the first ascent by Edmund Hillary and Tenzing Norgay in 1953.

Most Die While Descending

Most climbers die while descending the upper slopes of Mount Everest -- often after having reached the summit -- in the area above 8,000 meters called the "Death Zone." The high elevation and corresponding lack of oxygen coupled with extreme temperatures and weather together with some dangerous icefalls that are more active later in the afternoon create a greater risk of death than on the ascent.

More People Equals More Risk

The sheer number of people that attempt to climb Mount Everest every year also increases the risk factor. More people means the potential for fatal traffic jams at key sections of the ascent, such as the Hillary Step on the South Col Route or long lines of climbers following in each other footsteps.

One Death for Every 10 Ascents Prior to 2007

An analysis of the 212 deaths that happened during the 86-year period from 1921 to 2006 indicates some interesting facts. Most deaths -- 192 -- occurred above Base Camp, where the technical climbing begins. The overall mortality rate was 1.3 percent, with the rate for climbers (mostly non-native) at 1.6 percent and the rate for Sherpas, natives of the region and usually acclimatized to high elevations, at 1.1 percent. The annual death rate was generally unchanged over the history of climbing on Mount Everest until 2007 -- one death occurs for every ten successful ascents. Since 2007 as traffic on the mountain and the number of tour companies offering climbing packages to anyone with the money and inclination to try it, the death rate has increased.

Two Ways to Die on Mt. Everest

There are two ways of categorizing death on Mount Everest:-traumatic and non-traumatic. Traumatic deaths occur from the usual hazards of mountaineering-falls, avalanches, and extreme weather. These are, however, unusual. Traumatic death injuries usually occur on the lower slopes of Mount Everest rather than up high.

Most Die from Non-Traumatic Causes

Most Everest climbers die from non-traumatic causes. Climbers usually die on Mount Everest simply from the effects of exhaustion as well as injuries. Many climbers die from altitude-related illnesses, usually high altitude cerebral edema (HACE) and high altitude pulmonary edema (HAPE).

Fatigue Causes Death

One of the main factors in Everest climbing deaths is excessive fatigue. Climbers, who probably should not be making a summit bid because of their physical condition or inadequate acclimatization, set out from the South Col on their summit day but lag behind other climbers so that they arrive at the summit late in the day and later than a safe turn-around time. On the descent, they may simply sit down or become incapacitated by low temperatures, bad weather or fatigue. Resting may seem like the right thing to, but rapidly dropping temperatures late in the day high on the mountain pose additional and sometimes fatal dangers.

Along with extreme fatigue, many Everest climbers die after developing symptoms -- loss of coordination, confusion, lack of judgment and even unconsciousness -- of high-altitude cerebral edema (HACE). HACE often occurs at high elevations when the brain swells from the leakage of cerebral blood vessels.

Death of David Sharp

There are many tragic stories like that of British climber David Sharp, who sat down under an overhang 1,500 feet below the summit on May 15, 2006, after successfully climbing Mount Everest. He was extremely tired after a long summit day and began freezing in place as he sat there. As many as 40 climbers trudged past him, believing him already dead or not wanting to rescue him, on one of the coldest nights that spring. A party passed him at 1 in the morning, saw he was breathing still, but continued on to the summit since they didn't feel they could evacuate him. Sharp continued freezing through the night and the next morning. He had no gloves on and was likely hypoxic -- basically, a lack of oxygen that unless quickly reversed culminates in death.

Hillary Lambasts Callous Everest Climbers

Sharp's death created a huge storm of controversy over what was considered the callous attitude of the many climbers who passed the dying man yet made no attempt to rescue him, feeling that it would jeopardize their own ascent of the mountain. Sir Edmund Hillary, who made the first ascent of Mount Everest in 1953, said it was unacceptable to leave another climber to die. Hillary told a New Zealand newspaper: "I think the whole attitude towards climbing Mount Everest has become rather horrifying. The people just want to get to the top. It was wrong if there was a man suffering altitude problems and was huddled under a rock, just to lift your hat, say good morning and pass on by."