11 of the Earth's Strangest Mysteries That Still Haven't Been Solved
Posted on Jul 11, 2016
There's a lot of very strange things that happened here on Earth, but some of them lack a reasonable explanation. Check out this list of mysteries that haven't been solved.
1. The Yonaguni - Japan
These flat-edged, 90-degree structures are located off the shores of Yonaguni. However, it is still unclear whether these are man-made or natural formations.