Stonehenge practically radiates mystery. Who built it? Why? And how?
Now, there are some new questions: Why did the Altar Stone — a 6-ton cap for the neolithic monument — come from a site in Scotland about 450 miles away? And how was it moved from its mine to the Salisbury Plain site?
A team of scientists raised these notions in a Nature report that says the stone hails from Scotland, not Wales, as had been previously thought.
