17. D.B. Copper Sky Ransom
After the exchange and the plane went airborne, Cooper parachuted out with his ransom. While many believe he died, his body nor the money were ever found.
16. Nazca Geoglyphs
These lines etched deep into the Nazca Desert in Peru are a source of intrigue and wonder around the world. The designs range from humans, trees, and even animals. The truly amazing thing is that many of these images are over 1,000 feet in length. There has yet to be a single, persuasive explanation of who is responsible for them.
15. Escape From Alcatraz
In June 1962, what many considered the impossible happened. Three men managed to escape from the Alcatraz prison. However, that’s not where the story ends. While authorities claimed the prisoners drowned while swimming the San Fransisco Bay, no bodies were ever found.
Later studies have suggested that the prisoners could have survived their escape attempt. However, the mystery of their fate remains.