A group was formed for a ski trek across the northern Urals in Sverdlovsk Oblast. The original group, led by Igor Dyatlov, consisted of eight men and two women. Most were students or graduates of Ural Polytechnical Institute, now Ural Federal University:

• Igor Alekseievich Dyatlov, the group’s leader, born January 13, 1936

• Yuri Nikolaievich Doroshenko, born January 29, 1938

• Lyudmila Alexandrovna Dubinina, born May 12, 1938

• Yuri (Georgiy) Alexeievich Krivonischenko, born February 7, 1935

• Alexander Sergeievich Kolevatov, born November 16, 1934

• Zinaida Alekseevna Kolmogorova, born January 12, 1937

• Rustem Vladimirovich Slobodin, born January 11, 1936

• Nicolai Vladimirovich Thibeaux-Brignolles, born July 8, 1935

• Semyon (Alexander) Alekseevich Zolotariov, born February 2, 1921

• Yuri Yefimovich Yudin, born July 19, 1937, died April 27, 2013

The goal of the expedition was to reach Otorten which in Mansi language means “don’t go there”, a mountain 10 kilometres (6.2 mi) north of the site of the incident. This route, in February, was estimated as Category III, the most difficult. All members were experienced in long ski tours and mountain expeditions.

The group arrived by train at Ivdel, a city at the centre of the northern province of Sverdlovsk Oblast on January 25. They then took a truck to Vizhai – the last inhabited settlement so far north. They started their march toward Otorten from Vizhai on January 27. The next day, one of the members, Yuri Yudin, was forced to go back due to illness. The remaining group of nine people continued the trek.

Diaries and cameras found around their last campsite made it possible to track the group’s route up to the day preceding the incident. On January 31, the group arrived at the edge of a highland area and began to prepare for climbing. In a wooded valley they cached surplus food and equipment that would be used for the trip back. The following day (February 1), the hikers started to move through the pass. It seems they planned to get over the pass and make camp for the next night on the opposite side, but because of worsening weather conditions – snowstorms and decreasing visibility – they lost their direction and deviated west, up towards the top of Kholat Syakhl. When they realized their mistake, the group decided to stop and set up camp there on the slope of the mountain, rather than moving 1.5 kilometres (0.93 mi) downhill to a forested area which would have offered some shelter from the elements. Yudin postulated that “Dyatlov probably did not want to lose the altitude they had gained, or he decided to practice camping on the mountain slope.”

On February 26, the searchers found the group’s abandoned and badly damaged tent on Kholat Syakhl. The campsite baffled the search party. Mikhail Sharavin, the student who found the tent, said “the tent was half torn down and covered with snow. It was empty, and all the group’s belongings and shoes had been left behind.” Investigators said the tent had been cut open from inside. Eight or nine sets of footprints, left by people who were wearing only socks, a single shoe or were even barefoot, could be followed, leading down toward the edge of a nearby woods, on the opposite side of the pass, 1.5 kilometres (0.93 mi) to the north-east. However, after 500 metres (1,600 ft) these tracks were covered with snow.

At the forest’s edge, under a large cedar, the searchers found the visible remains of a small fire, along with the first two bodies, those of Krivonischenko and Doroshenko, shoeless and dressed only in their underwear. The branches on the tree were broken up to five metres high, suggesting that one of the skiers had climbed up to look for something, perhaps the camp. Between the cedar and the camp the searchers found three more corpses: Dyatlov, Kolmogorova and Slobodin, who seemed to have died in poses suggesting that they were attempting to return to the tent. They were found separately at distances of 300, 480 and 630 metres from the tree.

Searching for the remaining four travelers took more than two months. They were finally found on May 4 under four metres of snow in a ravine 75 metres farther into the woods from the cedar tree. These four were better dressed than the others, and there were signs that those who had died first had apparently relinquished their clothes to the others. Zolotariov was wearing Dubinina’s faux fur coat and hat, while Dubinina’s foot was wrapped in a piece of Krivonishenko’s wool pants. Another notable find besides the four remaining hikers was a camera around Zolotariov’s neck. The camera was not reported as having been part of the equipment. Also, the film in the camera was reported to have been damaged by water.

A legal inquest started immediately after finding the first five bodies. A medical examination found no injuries which might have led to their deaths, and it was eventually concluded that they had all died of hypothermia. Slobodin had a small crack in his skull, but it was not thought to be a fatal wound.

An examination of the four bodies which were found in May shifted the narrative as to what had occurred during the incident. Three of the ski hikers had fatal injuries: Thibeaux-Brignolles had major skull damage, and both Dubinina and Zolotarev had major chest fractures. According to Dr. Boris Vozrozhdenny, the force required to cause such damage would have been extremely high, comparing it to the force of a car crash. Notably, the bodies had no external wounds related to the bone fractures, as if they had been subjected to a high level of pressure.

However, major external injuries were found on Dubinina, who was missing her tongue, eyes, part of the lips, as well as facial tissue and a fragment of skullbone; she also had extensive skin maceration on the hands. It was claimed that Dubinina was found lying face down in a small stream that ran under the snow and that her external injuries were in line with putrefaction in a wet environment, and were unlikely to be related to her death.

There was initial speculation that the indigenous Mansi people might have attacked and murdered the group for encroaching upon their lands, but investigation indicated that the nature of their deaths did not support this hypothesis; the hikers’ footprints alone were visible, and they showed no sign of hand-to-hand struggle.

• Six of the group members died of hypothermia and three of fatal injuries.

• There were no indications of other people nearby on Kholat Syakhl apart from the nine travelers.

• The tent had been ripped open from within.

• The victims had died 6 to 8 hours after their last meal.

• Traces from the camp showed that all group members left the campsite of their own accord, on foot.

• To dispel the theory of an attack by the indigenous Mansi people, Dr. Boris Vozrozhdenny stated that the fatal injuries of the three bodies could not have been caused by another human being, “because the force of the blows had been too strong and no soft tissue had been damaged”.

• Forensic radiation tests had shown high doses of radioactive contamination on the clothes of a few victims.

• Released documents contained no information about the condition of the skiers’ internal organs.

• There were no survivors of the incident.

In 1967, Sverdlovsk writer and journalist Yuri Yarovoi published the novel “Of the Highest Degree of Complexity”, inspired by the incident. Yarovoi had been involved in the search for Dyatlov’s group and at the inquest as an official photographer during both the search and the initial stage of the investigation, and so had insight into the events. The book was written during the Soviet era when details of the accident were kept secret and Yarovoi avoided revealing anything beyond the official position and well-known facts.

The book romanticized the accident and had a much more optimistic end than the real events – only the group leader was found deceased. Yarovoi’s colleagues say that he had alternative versions of the novel, but both were declined because of censorship. Since Yarovoi’s death in 1980, all his archives, including photos, diaries and manuscripts, have been lost.

Anatoly Gushchin summarized his research in the book “The Price of State Secrets Is Nine Lives”. Some researchers criticized the novel due to its concentration on the speculative theory of a Soviet secret weapon experiment, but its publication led to public discussion, stimulated by interest in the paranormal. Indeed, many of those who had remained silent for thirty years reported new facts about the accident. One of them was the former police officer, Lev Ivanov, who led the official inquest in 1959. In 1990, he published an article which included his admission that the investigation team had no rational explanation for the accident. He also stated that, after his team reported that they had seen flying spheres, he then received direct orders from high-ranking regional officials to dismiss this claim.

In 2000, a regional television company produced the documentary film “The Mystery of Dyatlov Pass”. With the help of the film crew, a Yekaterinburg writer, Anna Matveyeva, published a fiction/documentary novella of the same name. A large part of the book includes broad quotations from the official case, diaries of victims, interviews with searchers and other documentaries collected by the film-makers. The narrative line of the book details the everyday life and thoughts of a modern woman (an alter ego of the author herself) who attempts to resolve the case.

Despite its fictional narrative, Matveyeva’s book remains the largest source of documentary materials ever made available to the public regarding the incident. In addition, the pages of the case files and other documentaries (in photocopies and transcripts) are gradually being published on web forums for enthusiastic researchers.

A Dyatlov Foundation was founded in Yekaterinburg, with the help of Ural State Technical University, led by Yuri Kuntsevitch. The foundation’s stated aim is to convince current Russian officials to reopen the investigation of the case and to maintain the Dyatlov Museum to preserve the memory of the dead hikers.

The theory that an avalanche caused the hikers’ deaths, while initially popular, has since been questioned. Reviewing the “Yeti” hypothesis, American skeptic author Benjamin Radford’s suggests as more plausible:

“that the group woke up in a panic and cut their way out the tent either because an avalanche had covered the entrance to their tent or because they were scared that an avalanche was imminent (better to have a potentially repairable slit in a tent than risk being buried alive in it under tons of snow). They were poorly clothed because they had been sleeping, and ran to the safety of the nearby woods where trees would help slow oncoming snow. In the darkness of night they got separated into two or three groups; one group made a fire (hence the burned hands) while the others tried to return to the tent to recover their clothing, since the danger had apparently passed. But it was too cold, and they all froze to death before they could locate their tent in the darkness. At some point some of the clothes may have been recovered or swapped from the dead, but at any rate the group of four whose bodies were most severely damaged were caught in an avalanche and buried under 13 feet of snow (more than enough to account for the ‘compelling natural force’ the medical examiner described). Dubinina’s tongue was likely removed by scavengers and ordinary predation.”

Evidence contradicting the avalanche theory includes:

• The location of the incident did not have any obvious signs of an avalanche having taken place. An avalanche would have left certain patterns and debris distributed over a wide area. The bodies found within ten days of the event were covered with a very shallow layer of snow and, had there been an avalanche of sufficient strength to sweep away the second party, these bodies would have been swept away as well; this would have caused more serious and different injuries in the process and would have damaged the tree line.

• Over a hundred expeditions to the region were held since the incident, and none of them ever reported conditions that might create an avalanche. A study of the area using up-to-date terrain-related physics revealed that the location was entirely unlikely for such an avalanche to have occurred. The “dangerous conditions” found in another nearby area (which had significantly steeper slopes and cornices) were observed in April and May when the snowfalls of winter were melting. During February, when the incident occurred, there were no such conditions.

• An analysis of the terrain, the slope and the incline indicates that even if there could have been a very specific avalanche that circumvents the other criticisms, its trajectory would have bypassed the tent. It had collapsed laterally but not horizontally.

• Dyatlov was an experienced skier and the much older Alexander Zolotarev was studying for his Masters Certificate in ski instruction and mountain hiking. Neither of these two men would have been likely to camp anywhere in the path of a possible avalanche.

In the numerous speculative theories surrounding the mysterious case, it is frequently mentioned that the name of the hikers’ ultimate destination, the mountain Otorten, means “don’t go there” in Mansi language and that the name of the neighbouring mountain on which they died, Kholat Syakhl, means “mountain of the dead”, suggesting that the general area was known to the local Mansi tribe as dangerous or “cursed”. In fact, Kholat Syakhl correctly translates as “dead mountain”, with “dead” referring to the absence of game. According to investigator Donnie Eichar, Otorten: