For years, scientists have been plagued by three unanswered questions related to Stonehenge: 1) Who built it? 2) Why was it built? and 3) Where did the stones used to construct it come from? Now, they've come up with an answer to one of those questions.
Using portable X-ray fluorescence spectrometry to analyze the huge sandstone boulders, scientists have determined they came from West Woods in the English county of Wiltshire, just more than 15 miles away from the Stonehenge site. They believe the stones were used to build the site's first "henge" monument about 5,000 years ago, and then to construct the stone circle in 2,500 B.C.
Unfortunately, the determination has created another unanswered question: How did an ancient civilization manage to transport 25-ton boulders 15 miles?