During the late evening of 1 February 1959 to the early morning of 2 February, something very strange happened to nine experienced skiers in the Ural Mountains of the Soviet Union. Whatever happened to these 7 men and 2 women, the consequences cost them their lives.
The investigation into their deaths seemed to show that the nine fled the camp they had set up in sudden terror. The group fled towards a thick forest about a kilometer and a half away (about 1 mile). They were in such a rush to flee, they didn't even try to open the tent, which was tied shut against the wind and snow-instead slashing the tent open wih their knives! When they dashed down the snowy slope towards the thick forest, they left behind such essentials as skis, food and warm coats. They didn't have a chance of surviving in the forest where bitterly cold temperatures hovered around -30 C (-22F).
The investigators at the time offered the explanation which didn't really explain anything, that "a compelling unknown force" caused the deaths of the group. The area-now known as "The Dyatlov Pass" in honor of the fallen group and their leader was then shut off to amateur sportsmen for "reasons of safety."
There would have been a tenth member in the group that fateful eve/morn had he not fallen ill and turned back-Yuri Yudin. "If I had a chance to ask God just one question, it would be: "What really happened to my friends that night?" says Yudin. 
Yudin and his nine comrades had left on their journey on 23 January 1959. Their destination was Otorten Mountain in the northern Urals. Yudin and eight of the other members of the group were either students or graduates of the Ural Polytechnic Institute of Sverdlovsk (now called Ekaterinberg-the city where the Tsar and his family were executed on the orders of V.I. Lenin in 1918).
The members of the group who perished are as follows: Igor Dyatlov, 23, and leader of the group=well respected for his expertise in cross-country skiing and mountaineering; Georgy Kolvonishenko (24), Yuri Doroshenko (24), Zina Kolmogoreva (22), Rustem Slobodin (23), Nicolas Thibeaux-Brignollet (24), Ludmila Dubinina (21), Alexandr Kolevatov (25) and Alexandr Zolotaryov, quite a bit older than the rest at 37.
Some silly rumours concerning Zolotaryov's involvement with the group began (as they will in these unexplained cases) saying he was either a "rather mysterious" or "unexplained" addition to the group. This was simply ridiculous. Zolotaryov had simply requested to go along because of his interest in the sport. Dyatlov had been initially reluctant to take him, but Zolotaryov had proven himself to be a very experienced sportsmen and came with a recommendatation from some of Dyatlov's own friends.
"Sports Tourism" had become very popular in the USSR after the years of austerity and privations caused by WWII and Stalin. Under Nikita Khrushchev's leadership, the USSR moved away from the extreme repression and terror under Stalin starting with Khrushchev's "Secret Speech" to the Twentieth Communist Party Congress of the Soviet Union in 1956. The Soviet Union was also experiencing great economic growth during the Khrushchev years (1955-1964), which allowed Soviet citizens to pursue other interests. Another reason sports tourism flourished was its apolitical nature. 
Upon leaving on 23 January, the initial group of ten left for what was supposed to be a three-week journey. They travelled by train to Ivdel, arriving on 25 January. Then they went to Vizhay-the last inhabited settlement before the snow-covered wilderness between them and Otorten. On 28 January 1959, Yuri Yudin became ill and had to turn back, leaving the nine to proceed without him. This was the last time he saw his friends alive.
Events after Yudin's departure can only be reconstructed from the diaries and photographs left by the group, and the investigation into the incident. On 31 January the group reached the river Auspia, where they set up a base at the edge of the highland area, and left food and equipment there for the return journey. From here, they began climbing the pass towards Otorten on 1 February 1959.
For some reason-most likely bad weather conditions causing them to become disoriented-the found themselves on the slopes of the moutain Kholat Syakh, at a height of around 3600 feet (1100 meters). They pitched their tent here around 5 p.m. on 1 February, although if they had travelled just about another mile (1.5 km) down the moutain, they would have had some greater shelter from the bad weather in a forest.
The last diary entry made by the group indicated they were in good -even terrific spirits. The next day they planned to continue on to Otorten, about 6 miles (10 kilometers) to the north, before returning to their base camp.
What happened to the group during that tragic timeframe from the late evening of the first to the early morning of the second is of course, a complete mystery. There have been loads upon loads of unsubstantiated claims and rumours piled upon this case. Everything from alien creatures, secret military testing gone wrong, some members of the groups corpses were said to have a strange orange-tan color, revenge by an indigenous tribe called the Mansi for daring to intrude upon their sacred territory (there was not a shred of evidence to support this theory-absolutely no evidence of anyone besides the original members of the group was found), injuries on some of the corpses were said to be only explained by "high-pressure" concussion type events (simply untrue), high levels of radiation also was said to have been found on some of the bodies-radiation was detected-but it was low-level and explainable by natural forces, the Yeti or Almasty (abominable snowmen), there were even rumours that the party had somehow fallen prey to subterranean Russian gnomes-perhaps similar to Richard Shavers' "Deros"!
Apparently there were reports of mysterious "bright flying spheres" in the area around the general time (February-March 1959) of the tragic deaths. However, even if true, these lights can in no way be linked to this case with what we know about it. Perhaps a bit more should be said about the local indigenous people- the Mansi. When one or more investigators thought of the Mansi as suspects, they may have been thinking of an incident in the 1930s, when Mansi shamans reportedly drowned a female geologist for trespassing on land they considered sacred. However, even though both mountains related to the Dyatlov expedition were known to the Mansi, neither are considered a sacred or taboo site. There is the chilling coincidence that Otorten means "don't go there" in the Mansi language, and Kholat-Syakhl means, even more chillingly "Mountain of the Dead." These Mansi names are probably more related to practical warnings for the nomadic Mansi tan any sort of tribal mythology or curse. 
Here are some observations from the Aquiziam site: (a) Ludmila Dubinina's tongue was not ripped out it was degraded through natural processes. (b) The radiation was inconsequential (c) The area was not sealed off to everyone-only amateur sports groups (d) The case was never classified (e) There are currently no records of any experiemental aircraft being tested in the area in 1959. (f) There is no evidence (now or then) that the area was used to test weapons. However, this doesn't rule out secret testing. (g) Photographs thought to be missile parts have turned out to be old radar units. (h) The "mysterious" envelope contained only general correspondence. (i) Photographs show that any discoloration of the bodies was wholly normal. (j) The injuries discovered are explainable and consistent with those that might be expected to occur in a group of desperate and clearly frightened people that had been stumbling around in dangerous conditions in the dark. (k) There is absolutely no evidence for crashed UFOs, Concussion Weapons, Mad Mansi, or Russian Death Squads. (l) All the physical evidence found at the time and subsequent analysis and testing indicates that there was no avalanche. However, at least one person involved with this case still believes that an avalanche was the cause.
And finally, from the Aquiziam site: "However, these now broadly accepted facts do not diminish the mystery-in a strange way they enhance it. As we have repeatedly said throughout these pages...Why did nine, experienced and sensible, ski-hikers abandon their tent in such a hurry and in weather conditions that were hostile and almost certain to lead to their deaths? What really happened that night?"
More here and here Infrasound was put forth as a possible explanation on the Aquiziam site (BTW-I would very much recommend going through all of Aquiziam's pages on this strange incident and the other links to get a "feel" for the case!) and I wonder if this is a good candidate? Infrasound is very-low frequency sound waves that can make the human brain think something supernatural is going on, i.e., produce terrifying and eerie feelings in people. However, I also have to wonder if a group such as these nine people would have been suggestible to this feeling? These were obviously no "Nervous Nellies" (like me- LOL). I will have to research infrasound further to see if this makes sense and will come back with a link for infrasound. All the best to anyone stopping by!
The first image is a picture made showing the original picture of the Dyatlov Party's tent with the area they went to when they fled in terror. The second image is of the Dyatlov group having fun-not at the final campsite. The third image is of the original search team. The last image is of 23-year-old Igor Dyatlov. OK- here is the link to infrasound information-I will try to find more on it!
