Ships and planes have disappeared in the Bermuda Triangle in the western North Atlantic Ocean. The inexplicable events in this area remain unexplained despite significant inquiry.
These massive Egyptian structures' design and construction methods are still debated.
The Nazca Lines are massive geoglyphs in southern Peru's Nazca Desert. These elaborate designs, visible only from the sky, have no known designers or purpose.
15th-century illustrated book, contains indecipherable markings and images. Researchers are still unsure of its origin, author, and meaning.
England's prehistoric Stonehenge is a circle of huge standing stones. No one knows why it was built or how.
North Americans and Pacific Northwesterners have seen Bigfoot or Sasquatch for decades. No sightings or searches have found it.
In 1971, D.B. Cooper kidnapped a commercial jet, demanded a ransom, and parachuted off. One of air piracy's most notorious unsolved instances is D.B. Cooper's identify and fate.