In early February of 1959, nine experienced ski hikers from from the Ural Polytechnical Institute headed into the northern Ural Mountains in the Soviet Union for a challenging expedition. When they hadn’t returned to their homes more than a week later, Soviet officials organized multiple search parties to find the scholars.

Instead, the searchers uncovered a mystery that persists to this day.

The hikers’ camp at Dyatlov Pass was mostly intact, but their tent had been cut open from the inside, and the occupants had dashed out into the cold and snow, most of them only partly dressed. All nine perished, some from hypothermia and some from injuries that were described as having been inflicted by “something” with superhuman strength.

So just what happened to this unlucky party of adventure seekers?

A multitude of Dyatlov Pass incident theories leave a fascinating trail through all reaches of the unknown from UFOs and cryptids, to warfare and government cover-ups.

Here are some of the more prevalent possibilities.

Avalanche

Anytime a bunch of people die in cold, snowy, mountainous climes, you have to consider the possibility that an avalanche is to blame. In the Dyatlov case, the avalanche theory supposes that the hikers were compelled to slash their way out of their tent because an avalanche had already blocked the tent opening or because they heard crackling ice and panicked. Once out of the tent, they ran for cover in the woods but, being lightly clothed for nighttime, became hypothermic and disoriented, eventually succumbing to the cold.

Subsequent investigations, though, have found little evidence that an avalanche occurred that fateful night or that the area is particularly susceptible to avalanches.

avalanche

Infrasound

An infrasound is an ultra low-frequency sound that would normally be inaudible to humans but which may be perceived if it’s delivered with sufficient sound pressure. The phenomenon is often observed in relation to earthquakes, nuclear detonations, and other seismic-scale activities and can induce panic attacks in humans. In relation to Dyatlov, one theory claims that a wind vortex capable of producing infrasound may have developed in the nearby¬† Mountains, causing the hikers to flee their tent and run with abandon to avoid their unseen tormentor.

Parachute Mines

It is known that the Russian military conducted tests with parachute mines in the general area of Dyatlov Pass during the 1950s. These types of mines are dropped from planes and float toward the earth, detonating several feet before impact. The damage they can cause to humans would likely be similar to the injuries suffered by the hikers and might account for the radioactive materials detected on some of the victims’ clothes. However, the radiation from such devices would have affected all of the hikers and their equipment, but only a few of them exhibited evidence of radioactivity.

Paradoxical Undressing

As hypothermia sets in, people often become confused and do the exact opposite of what you might expect someone who is dying of exposure to do — they remove their clothes. This paradoxical undressing could account for the lack of clothing for six of the hikers, but others appear to have layered on additional articles after they ventured into the cold. And, even if paradoxical undressing contributed to the deaths, why did these people leave their tent in the first place?

Menk or Russian Yeti

Several years ago, the Discovery Channel aired a special called Yeti: The Killer Lives. In that program, investigators revealed that the first searchers to discover the campsite and bodies also encountered huge footprints that couldn’t have belonged to humans. They took photos of the prints, but those pics were allegedly gobbled into the bowels of Russian bureaucracy as part of a cover-up. Even with little else in the way of evidence, the report of large prints — which witnesses insist didn’t belong to any known animal — sparked theories about an attack by the Menk (sort of a Russian Bigfoot) or the Russian Yeti. It’s an intriguing, almost romantic, notion but without much to back it up.

Mansi Attack

The Mansi are an indigenous population living in Khanty-Mansia, with hunting grounds and sacred grounds at least relatively near the Dyatlov Pass. Early investigators put together a theory that had the hikers running afoul of a group of Mansi through either trespassing or a confrontation over another issue. With an intimate knowledge of the land, the Mansi would have had a clear advantage over a visiting group and would likely have outnumbered them, as well. But as easy as it might have been for Mansi to overwhelm the hikers, there is no real evidence that happened, and the victims’ belongings were left largely intact. It would have made little sense for the Mansi to kill the hikers and not make use of their belongings since goods of all type were hard to come by in the rough and rugged country.

Animal Attack

Sometimes the simplest explanation is the best, and the Dyatlov hikers certainly wouldn’t be the first to have met their end at the hand of¬†known wild animals. But the lack of tracks and claw or teeth marks that might indicate the involvement of, say, a bear make a simple animal attack seem unlikely as the cause of these deaths.

Romance Gone Wrong

One of the seedier ideas about what happened at Dyatlov is that two or more members of the group became engaged in some sort of physical relationship, which caused jealousy to spark among others in the party. Coupled with the disorienting cold, these flaring tempers led to irrational behavior, melee, and, ultimately, the death of all nine hikers. If this sounds implausible to you, you’re not alone in that opinion.

KGB Controlled Environment

One classic Cold War theory about Dyatlov holds that three of the skiers were KGB agents sent to spy on a bevy of CIA spies who were set up in the area. Somehow, the CIA agents got wind of the plan or otherwise got the upper hand and killed the KGB guys and their unwitting accomplices. While very cloak and dagger, this story leaves plenty of holes about the appearance of the camp and the final condition of the hikers’ bodies.

Mistaken Identity

Another intriguing theory is that the hikers were mistaken for escaped prisoners from a local Gulag and handled accordingly. While most political prisoners were released by 1956, there were still pockets of captives. You might imagine that prison masters would be none too pleased with a band of escapees, so it wouldn’t be too surprising if they leveled swift and violent punishment. Still, why would the hikers cut their way out of the tent?

Mushrooms

The area near Dyatlov Pass is home to a toxic breed of mushroom called the Agaric Fly, which is merely hallucinogenic and psychedelic when dried out. Some theorize that local hunters, high on the ‘shrooms, happened upon the band of hikers and flew into a homicidal frenzy. Another ‘shroom-fueled theory has the hikers themselves partaking of Agaric Fly and becoming disoriented and, ultimately, dead.

ufo dyatlov

Close Encounter

Several reports of strange lights and sounds, and an admission by Soviet forces that they launched rockets nearby have led some conspiracists to point toward and alien encounter as the ultimate cause of demise for the hapless Dyatlov band. In particular, although the Soviets claim their rockets weren’t headed toward Kholat Syakhl, several eyewitnesses place strange light orbs in that vicinity on February 1. Could a UFO have scared the hikers out of their tent and caused them to lose their way in the frigid wilderness?

Secret Launches

A more terrestrial but still astronomical possibility is that the hiking party ran afoul of secret Soviet rocket launches in some way. Though no records of launches for February 1 or 2 have been unearthed, locals insist the area was a hotbed of secret military meetings and, ultimately, rocket launches. Perhaps the hikers saw something they shouldn’t have and had to be eliminated? Or maybe something about the Soviet launches themselves killed the campers? Certainly, you can imagine how a nearby rocket launch in the middle of the night might send you into a panic if you were sound asleep at the time!

Teleportation

Although pure fantasy (right?), a 2013 horror movie called Devil’s Pass presented an explanation that involves teleportation and demons from another dimension. Check out the trailer below:

Lightning Strike

This one is pretty complicated but basically suggests that there was some sort of lightning show on display as the hikers tried to sleep on that fateful night. Anxious to watch what was happening, they cut viewing slits in the tent and set up a camera on a makeshift tripod, likely not aware that their prey — the lightning — would become the predator. Alas, lightning struck near their ravine-bounded tent, vaporizing snow and ice and generating an explosion that killed six of the hikers. The other also subsequently perished as they tried to recover from the catastrophe.

Stove Malfunction

Part of the skiers’ arsenal of supplies was a homemade stove that kept the tent warm while venting into the outdoors. This theory supposes that the stove reignited as the party slept, filling the tent with smoke. The campers tried to air out the tent by cutting slits in it and, when they lost control, the bolted into the snow. Intoxicated by the smoke, they soon became disoriented and perished in the cold.

Gravity Fluctuation

Some Russian scientists believe that the area around the Dyatlov Pass is subject to occasional but dramatic gravity fluctuations. They theorize that the hikers were unlucky enough to set up camp just as a low-gravity wave passed through and were essentially lifted/sucked from the tent and expelled into the night to face their doom. The best part about this theory is that it suddenly makes the teleportation scenario seem more likely.

Fireballs

In 1990, one of the original investigators of the Dyatlov Pass incident put forth a theory that involves massive fireballs in the sky. A sort of amalgamation of the ball lightning and UFO theories, this one maintains that several witness reported seeing the fireballs crossing the sky in the general area of Dyatlov. At some point, the balls either exploded or began to radiate toxic energy close enough to the hikers to cause their deaths.