Nine Hikers Cut Their Tent Open From the Inside and Ran Into the Snow. The Dyatlov Pass Incident.

On February 26, 1959, a search party climbing a bare, windswept slope in the northern Ural Mountains of the Soviet Union found a tent.

It was half-buried in snow and badly damaged. And it had been cut open. From the inside.

Inside were boots, coats and supplies.

Leading away from it, down the slope, were footprints. Nine sets. Some of the people who made them were wearing only socks. Some had one shoe. Some were barefoot.

In temperatures far below freezing, nine experienced hikers had cut their way out of their own shelter and walked away into the dark.

None of them survived.

The Soviet investigation said they died because of "a compelling natural force." For sixty years, people have argued about what that force was.

The group

The hikers were students and graduates of the Ural Polytechnical Institute in Sverdlovsk, the city now called Yekaterinburg.

Their leader was Igor Dyatlov, twenty-three.

With him were Yuri Doroshenko, twenty-one. Lyudmila Dubinina, twenty. Georgiy Krivonishenko, twenty-three. Alexander Kolevatov, twenty-four. Zinaida Kolmogorova, twenty-two. Rustem Slobodin, twenty-three. Nikolai Thibeaux-Brignolles, twenty-three. And the oldest, Semyon Zolotaryov, thirty-eight.

There was also a tenth member, Yuri Yudin, twenty-one. Remember that name.

All of them had hiking and skiing experience. The plan was to ski to a mountain called Otorten, in the far north of the Sverdlovsk region, in the middle of winter.

The route

On January 23, 1959, the group got its route book and left Sverdlovsk by train.

On January 25, they reached the town of Ivdel. On January 26, they rode a truck to Vizhai, the last inhabited settlement to the north. On January 27, they set off on skis.

On January 28, Yuri Yudin turned back. He had pain in his knee and joints and could not go on. He said goodbye to the others and headed home.

He was the only one who came back.

The other nine kept going. They kept diaries and took photographs along the way, which later let investigators follow them almost to the end. On January 31, they reached the edge of a highland area and left a cache of extra food and gear, to pick up on the way back.

Then, around February 1, they set up their tent on the slope of a mountain the local Mansi people call Kholat Syakhl.

The search

Dyatlov had arranged to send a telegram when the group got back to Vizhai. It was due by February 12.

It never came.

Delays were common on trips like this, so at first nobody panicked. By February 20, relatives were demanding a rescue. The institute sent teams of student and teacher volunteers. The army and police joined in later, with planes and helicopters.

On February 26, searchers found the tent.

The footprints

The tent had been cut open from the inside. Most of the group's warm clothing and boots were still in it.

The footprints led downhill, toward a forest about a kilometer and a half away. After about five hundred meters, the snow had covered them.

At the edge of the forest, under a large pine tree, searchers found the remains of a small fire, and the first two bodies: Krivonishenko and Doroshenko. They were barely dressed and barefoot.

Between the pine tree and the tent, three more bodies were found on the slope: Dyatlov, Kolmogorova and Slobodin. They seemed to have died while trying to get back to the tent.

All five died of hypothermia.

Four people were still missing.

The ravine

It took more than two months to find them.

On May 4, 1959, the last four were found under about four meters of snow, in a ravine about seventy-five meters from the pine tree.

They were Dubinina, Kolevatov, Thibeaux-Brignolles and Zolotaryov.

These four were better dressed. Some of them were wearing clothes that had belonged to the others, as if they had taken them from the bodies of their friends. Dubinina was wearing Krivonishenko's trousers.

And three of them had severe injuries.

Thibeaux-Brignolles had a major skull injury. Dubinina and Zolotaryov had major chest injuries, the kind investigators compared to the force of a car crash. Yet there were few outside wounds.

Some of the bodies in the ravine also had damage to the face. Because they had been lying in a stream, the forensic expert judged that damage happened after death.

"A compelling natural force"

The Soviet investigation closed in May 1959. It found no guilty party.

Its conclusion was that the hikers had died because of "a compelling natural force." It did not say what that force was.

The files were sent to a secret archive.

Some people were questioned early on, including local Mansi people, whose land this was. Investigators found no evidence of an attack.

Later, journalists who read the inquest files reported that traces of radiation had been found on some of the clothing. That claim comes secondhand, and its meaning has been argued over ever since.

Because the files were secret, and the details were strange, the theories multiplied.

The theories

Over the decades, people proposed almost everything.

Secret weapons tests. Parachute mines. A flare from an aircraft that the hikers mistook for a nuclear blast. Infrasound, very low sound made by wind, that could cause panic. A powerful downhill wind. An animal attack. A fight inside the group.

Investigators found no evidence for an attack by people or animals.

One fact explains some of the strangest details. People dying of severe hypothermia sometimes take off their clothes, because their body's temperature sense fails and they feel like they are burning. It is called paradoxical undressing. It may explain why some of the hikers were found so lightly dressed.

But it does not explain why they left the tent in the first place.

The avalanche answer

In February 2019, Russian authorities reopened the case. They considered three explanations: an avalanche, a slab avalanche, or a hurricane-strength wind. They ruled out murder.

On July 11, 2020, a Russian prosecutor announced the official cause of death. An avalanche.

Investigators said the group faced winds of up to twenty to thirty meters per second, heavy snow, and temperatures near minus forty. They said the campsite was poorly chosen, and that the group split up after the slide. The prosecutor said the hikers had made "a heroic struggle," but had no real chance to survive.

In January 2021, two scientists, Johan Gaume and Alexander Puzrin, published a study in the journal Communications Earth and Environment. Their computer simulation showed that a fairly small slab of snow, sliding from a slope above the tent, could damage it and cause injuries like the ones found in the ravine.

That would explain why they cut their way out. They thought more snow was coming, and they ran downhill to get away from it.

What we still don't know

Not everyone accepts the avalanche answer.

Critics point out that the search party did not report a clear avalanche debris field. They argue the slope is not steep enough for a dangerous slide. And a simulation can show what is possible, not what actually happened.

What we know is this. Nine young, experienced hikers abandoned their only shelter, in the middle of a freezing night, without their boots. Some of them built a fire and tried to survive. Some tried to get back to the tent. Some dug into a ravine and shared clothes from their friends who had already died.

And one man, Yuri Yudin, lived because his knee hurt. He died in 2013, still without an answer.

The pass where they died now carries the leader's name. Dyatlov Pass.

What do you think drove them out of that tent?