On February 4, 2019, Russian prosecutors announced that they were reopening the investigation into the Dyatlov Pass Incident. This is one of the most puzzling mysteries of the modern era.

In January 1959, Igor Dyatlov was a twenty-three-year-old radio engineering student at the Ural Polytechnical Institute, now known as the Ural Federal University. Dyatlov was an elite skier and hiker, and he assembled a group of nine fellow students to accompany him on a 16-day expedition that would cover 190 miles (305 km) across the North Ural mountains of Otorten and Kholat Syakhl.

Igor Dyatlov, Source: Public Domain

The eight men and two women all had Grade II-hiker certification with ski tour experience, and after completing the upcoming expedition, they would receive what at the time was the Soviet Union's highest certification possible, Grade III.

The trek begins

In the early morning of January 25, 1959, the group arrived by train at the town of Ivdel, then took a truck to Vizhai, the last inhabited settlement before their trek. There, they purchased loaves of bread to add to their supplies.

On January 27th, they began their trek, and the next day a member of the group, Yuri Yudin, complained of feeling unwell and returned to Vizhai.

Expedition team members, Source: Russian National Archives

The remaining nine continued on. They included Igor Dyatlov, 23, Yuri Doroshenko, 21, Lyudmila Dubinina, 20, Yuri Krivonischenko, 23, Alexander Kolevatov, 24, Zinaida Kolmogorova, 22, Rustem Slobodin, 23, Nikolai Thibeaux-Brignolles, 23, and Semyon Zolotaryov, 38.

Dyatlov Expedition members, Source: LEMMiNO/Youtube

The Pass

On January 31st, the group arrived at a wooded valley where they cached surplus food and equipment that they intended to use on the way back. The next day, February 1, 1959, they began to move through the pass that would come to be called the Dyatlov Pass.

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From what was recovered from expedition members' Dyatlov Pass photos and diaries, investigators were able to determine that the Russian hikers hoped to make camp that night on the opposite side of the pass. During that day however, snowstorms moved in and the group deviated to the west, ending up at the top of a mountain called Kholat Syakhl. In the language of the indigenous people, Kholat Syakhl means "Dead Mountain".

Rather than making their way down the mountain to a forested area, they chose to make camp on the mountain's slope. Temperatures that night were very cold, -25 to -30°C (-13 to -22°F), and the group shared one large tent.

Photo from Dyatlov's camera showing the last camp, Source: Public Domain

An overdue telegram

Dyatlov had arranged with Yudin that he would send a telegram once the group had returned to Vizhai, but when no telegram arrived on the agreed-upon date or for a week thereafter, Yudin alerted the authorities. The head of the Ural Polytechnical Institute assembled a rescue team comprised of students and teachers to look for the missing hikers. After what they found, the Soviet army got involved.

On February 26, 1959, the rescuers from the Ural Polytechnical Institute found the Dyatlov group's tent — it was cut in half, but from the inside. Within the tent were the group's belongings, including their shoes. Outside the tent, there were nine sets of footprints made by people who were wearing only socks, a single shoe, or were barefoot.

Tent cut from the inside, Source: Soviet investigators/Wikimedia Commons

The rescuers followed the footprints, some of which led down toward the edge of nearby woods 1.5 km (.93 miles) north-east of the tent. At the edge of the forest, under a large pine tree, the rescuers found the remains of a small fire and the shoeless bodies of Krivonischenko and Doroshenko who were wearing only their underwear.

Bodies of Doroshenko and Krivonischenko, Source: Public Domain

Above the bodies, branches on the pine tree were broken to a height of 5 meters (16 feet), indicating that at least one of the men had climbed up to look at something, perhaps the camp.

Between the pine tree and the camp the rescuers found three more bodies, those of Dyatlov, Kolomogorova, and Slobodin. They were lying several hundred meters from one another.

Bodies of Dyatlov, Kolomogorova and Slobodin, Source: Soviet National Archives

Despite intensive searching, rescuers didn't find the remaining four expedition members until May 4th. They were located 82 yards (75 meters) further into the woods from the pine tree, and three of the four were found wearing more clothing than the others. There were signs that as each of them died, their clothes were appropriated by those who were still alive.

Dubinina’s foot was found wrapped in a piece of Krivonischenko’s wool pants, and Zolotaryov was found wearing Dubinina’s coat and hat.

Unexplained injuries

It wasn't until autopsies were performed on all the expedition members that things took a turn toward the weird. Thibeaux-Brignolles had several fractures to his skull. Lyudmila Dubinina and Semyon Zolotaryov had major fractures of their chests, but none of these bodies showed any signs of external trauma.

The doctor examining the bodies described the force needed to cause the fractures as being comparable to a car crash. It was as if they had been subjected to a high level of pressure.

Bodies of Kolevatov, Zolotaryov, and Thibeaux-Brignoles, Source: Soviet National Archives

One body that did show signs of external trauma was that of Dubinina. She was missing her eyes, tongue, part of her lips, part of her face, and a fragment of her skull bone. The skin on her hands was macerated while Alexander Kolevatov's body showed no signs of injury.

Body of Dubinina, Source: Soviet National Archives

An attempt at an explanation

Authorities initially suggested that the group had been attacked by indigenous people in the area known as the Mansi, however, only the hikers' footprints were visible in the snow. Also, none of the hikers' bodies showed signs of a struggle.

Troubling questions were: Why were the expedition members only partially dressed? Why had they run into the snow wearing only socks or else barefoot?

While there were many Dyatlov Pass theories, an official inquest into the deaths found that:

Six members of the group died from hypothermia (from the cold), while three had fatal injuries.

At the time of the incident, there were no other people on Kholat Syakhl other than the Dyatlov group.

All expedition members died between 6 and 8 hours after eating their last meal.

and after eating their last meal. Three separate articles of clothing found on two of the bodies were radioactive.

The official inquest concluded that the hikers' deaths were the result of "a compelling natural force." According to the AFP news agency, the results of that inquest remained classified until the 1970s.

When the Russians reopened an investigation into the Dyatlov Pass Incident in February 2019, CNN reported that only three possible explanations for the deaths were being considered: an avalanche, a "snow slab" avalanche, or a hurricane.

Opposing an avalanche explanation are the fact that the area showed no signs of an avalanche having taken place, and the fact that the bodies that were found within 10 days of the incident were covered with only a very shallow layer of snow. Since the incident, over 100 expeditions to the same area have taken place, and none has ever reported an avalanche.

A "snow slab" avalanche occurs when a weak layer of snow lies beneath a snowpack. When this weak layer breaks off, it pulls all the layers on top of it down the slope. Alexander Zolotaryov was studying for his Masters Certificate in ski instruction and mountain hiking, and neither he nor Igor Dyatlov would have been likely to camp anywhere that could be in the path of a potential avalanche.

The possibility of a hurricane in the northern Ural Mountains is remote at best.

The aftermath of the disaster

Following the incident, the pass was named The Dyatlov Pass in honor of the group. At the Mikhajlov Cemetery at Yekaterinburg, a monument was erected for the nine students.

Monument to the students, Source: Artur Andrzej/Wikimedia Commons

In 1990, Russian Anatoly Gushchin published a book about the incident, The Price of State Secrets Is Nine Lives. In 2013, a Russian-British horror film directed by Renny Harlin and entitled The Dyatlov Pass Incident was released. Its name was eventually changed to Devil's Pass.

In 2015, the Russian band Kauan released an album entitled Sorni Nai which attempts to reconstruct the events leading up to the incident. While there are many mysteries remaining to be solved, The Dyatlov Pass incident continues to puzzle and fascinate all who come to learn of it.