A long line of climbers follow each other up Mt. Everest. Image: Ralf Dujmovits.

1996 was the deadliest year in the history of modern climbing on Mt. Everest. In one May weekend, eight people died when they were caught on the mountain in a storm. Over the course of the year, the death toll climbed to 15 total.

In the wake of that year, people tried to make sense of what had happened—particularly when it came to the May 10/11 deaths. All the reporting brought some internal mountaineering debates into the public eye in a big way for the first time. Is it really a good idea to treat Mt. Everest as an adventure-minded tourist attraction, suitable for anyone with a little climbing experience and enough money? What are the risks of having lots of inexperienced, guided trekkers up on the mountain at the same time? Do those climbers have enough climbing instincts to make the right decisions about going on or turning back when they're exhausted and under the influence of a low-oxygen environment? What can their guides do, under those circumstances, to force a right decision? Remember: This isn't a place where help is readily available if you get into trouble. Helicopters can only go so high up the mountain. And if you collapse, the chances of somebody else being able to carry you down are pretty slim.

These questions are likely to come back into the spotlight now. Between May 18th and 20th—last weekend—four people died on Mt. Everest. One is still missing. This time, there was no storm. Instead, the problems seem to be a combination of human error, "everyday" harsh conditions, and the fact that 300 people were trying to summit the mountain all at the same time.

Grayson Schaffer, an editor for Outside has been in the Everest Base Camp for the better part of a month. He's not attempting to climb up the mountain, himself. His story on the deaths is very much worth reading.

"THIS IS THE FIRST TIME I've seen it like this," says Onzchhu Sherpa, 31. Starting on the night of May 18 and going through the 20th, roughly 300 climbers, guides, and Sherpas crowded onto the upper slopes of Everest's Southeast Ridge. From the 19,000-foot shoulder of a neighboring peak, where I was watching, Everest appeared to be lit up like a Christmas tree with the headlamps of climbers converging from the mountain's north and south sides.

... What I can tell you is that the mood at Base Camp has been overridingly gloomy since the news of the mishaps first began trickling down the mountain. On the 19th the air may have been filled with the customary bell ringing that that signifies a team member has just radioed in from the summit, but later in the evening I heard loud sobs coming from the direction of the Korean camp. Even now, two days after the chaotic events, the details are foggy. That's because of inherently poor communications and the fact that many climbers are so exhausted and woozy from their efforts at altitude that they have a hard time even remembering what happened during their own climbs, let alone those of their teammates and strangers. With radio communications further hampered by geology and an endless stream of information that’s difficult to verify, it would be easier to report on a moon landing.

Read Grayson Shaffer's full account of the deaths on Mt. Everest