The Dyatlov Pass Incident, 1959

When investigators found the bodies of nine missing trekkers in the Artic tundra half-dressed and away from their tent for no apparent reason, it began perhaps the spookiest mystery in Russian history.

It was the depths of winter and 23-year-old Igor Alekseyevich Dyatlov with eight other fit, young men and women arrived at the town of Ivdel in Siberia’s nether regions.

They had come from the Ural Polytechnical Institute to complete a 190 mile (300km) training hike and the whole group were pretty much experts at operating in this harsh, hostile environment. Yet the mystery around their fates has led to no less than 75 theories to account for their demise.

Rescuers first on the scene and investigators of the day pieced together what they could: The group had passed through the Dyatlov Pass in a blizzard and got disoriented and lost. Realising they had taken the wrong route up the wrong mountain, they camped out in a single large tent on a mountain slope, in spite of some woodland being just one mile yonder, perhaps so that the team could practice making camp in the open.

Then something compelled the group to flee so desperately, they cut a hole in the tent side and so quickly, they didn’t have time to dress or even put on shoes to guard against the −30 °C (−22 °F) winter storm outside. They walked to the nearby copse of trees where two of them were found around a small fire in just their underwear.

Another three were found halfway back towards the tent, apparently trying to return once the danger, whatever it was, had passed. All had died from hypothermia. The other four were discovered later in the year once the snow had melted 75m (246ft) further in the woods and down a ravine. They were missing eyes and lips but also with severe chest injuries and a fatal skull injury.

So what had scared the group so much they fled the tent’s sanctuary under-dressed to certain death in the blizzard? Why had they split up? Were the other four’s injuries really due to falling into the ravine? …and why did one of the nine have heavy traces of radiation?

Reports around the event were highly censored, even by the Soviet’s standards and this only fuelled conspiracy theories and intrigue. Another group of hikers about 31 miles (50 km) south of the incident reported strange orange spheres in the sky to the north on the night of the incident. There are also claims military weapon tests may have been conducted nearby, which could’ve panicked the nine.

Other theories include everything from violent katabatic winds, infrasound, high winds blowing one member away and who the others attempted to rescue, to attack by local tribal people or even by a yeti.

The most plausible explanation, however, is that the group were alarmed by a slow-moving wall of snow known as a ‘snow slide’ which might have blocked the entrance and a fear of getting engulfed by the mass of snow forced them out. Regardless, the swirl of mystique around this incident compelled the Russian state to launch another investigation in 2019.