Sacsayhumán, Peru
Yet another hot spot for Peru. This time, the mystery lies within an ancient site where people used to live thousands of years ago. The masonry is so perfect that engineers and historians are baffled as to how it was made before any technology existed. Some of these walls are so secure that a piece of paper can't even penetrate a crack.
The Devil's Kettle
The Devil's Kettle is a popular hiking spot in Minnesota. The name refers to a waterfall that splits off into two different directions. One fall leads right into another river while the other goes into a deeo abyss. Researchers are uncertain as to where the water leads to, even after tons of research.