In 1959, nine experienced hikers died in the Ural Mountains and the cause of their death has never been entirely clear.
The group was hiking through the Soviet Union when overnight between 1 and 2 February, something caused them to cut their way out of their tents and rush out into the freezing cold conditions without wearing proper protection.
Six of them died from hypothermia while the other three had been killed by physical trauma - two of the bodies had missing eyes and one was found without a tongue.
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This was dubbed the 'Dyatlov Pass incident', named for the group leader Igor Dyatlov.
What exactly happened to them will likely never be known since none of them survived to tell the tale, and only the bodies and environment can really speak for them.
A YouTube simulation of what might have happened shows some of the gruesome details of the unsolved mystery.
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The simulation, created by Zach D. Films, depicts what the bodies may have looked like when the rescue team stumbled upon them.
Firstly, the tent was ripped open from the inside. They also found that all nine travellers were dead, with two - Lyudmila Dubinina and Semen Zolotarev - having empty eye sockets, while Dubinina was also missing her tongue.
Another had a twisted neck, while a different body had a fractured skull, though some showed signs of internal injuries.
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Some of the bodies were found out of the tent in nothing but socks and underwear, despite the freezing, snowy weather.
The dead hikers have been the fuel for all sorts of conspiracy theories which have fixated on details such as their tents being torn and the experience of the group.
A number of people claim that yetis are responsible for their deaths, though some theorise that some members of the group had connections to the KGB and were secretly on a mission to meet US agents.
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However, an investigation by the Russian prosecutor-general's office claims to have solved the mystery.
Andrei Kuryakov, the senior state prosecutor, said that they were in the way of an avalanche and attempted to shield themselves.
He claimed: "This was a natural avalanche limiter. They did everything right. But here is the second reason why the group was doomed.
"When they turned around, they could not see the tent. Visibility was 16 metres (52ft)."
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Kuryakov further explained: "It was a heroic fight. There was no panic, but they had no chance in these circumstances.”
Subjected to freezing temperatures of between -40°C and -45°C, those who had not been killed by this possible avalanche would have died from the cold rather quickly.
If this is really the way they died then it would have been a sudden, frightening and agonising experience for the nine hikers to suffer through.
A monument was later erected to commemorate the nine dead hikers.
Additional words by Josh Nair.
Topics: World News, Russia, Conspiracy Theory
Joe Harker