Dyatlov Pass

Between February 1 and 2 of 1959, nine Rusian hikers died in the northern Ural Mountains. They were all, to some degree, experienced hikers but sometime during the night, something caused them to flee from their campsite while wearing inadequate clothing.

This caused six of them to die of hypothermia, while the other three showed signs of physical trauma. Nobody knows up until this day what they saw and what ended their lives.