The exact cause of death and burial site of Genghis Khan is unknown, because all of the 2000 funeral guests and 800 soldiers were killed in order to preserve the secret.
16
In 1958, a nuclear bomb was lost somewhere along the swampy coast of Georgia. Its whereabouts remain a mystery to this day.
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There is a 600 year old 240 paged book called the Voynich Manuscript, that’s written language is still completely unknown today.
15
In 1987, a Chicago TV station had its broadcast interrupted by a pirate signal that shows a man in a Max Headroom mask mumbling and being spanked with a fly swatter. Despite investigations by the FCC and FBI, this became the only known incident in which a hacker interrupted a major TV broadcast without getting caught.
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