Stonehenge is an icon of prehistoric British culture, an enigma that has seduced archaeologists and tourists for centuries. Why is it here? What is its significance? And which forces inspired its creators? Now a group of international archaeologists led by the University of Birmingham and the Ludwig Boltzman Institute in Vienna believe that a new state-of-the-art approach is the key to unlocking Stonehenge's secrets. For four years the team have surveyed and mapped every monument, both visible a...