How a glacier and rising seas may have brought the six-tonne Altar Stone to Stonehenge

The four metre-long stone came from more than 400 miles away in north east Scotland

muratart/Shutterstock Built from stones weighing between 2 and 25 tonnes, the structure of Stonehenge demonstrates a scale of construction hard to imagine before the invention of the wheel. The mystery deepens when you consider that the stones are not from the local bedrock. So why these stones, and how did they get th