The Stonehenge Riverside Project team, which has been working on the Stonehenge (UK) site for the last 10 years, believe that the eight monuments which comprise the Stonehenge complex, may have been erected to unify the warring factions of the east and west of southern Britain. The theory is built on the fact that the material collection, shaping and erection would have been such a mammoth undertaking that it could only have been accomplished by thousands of individuals working together, to meet a common goal.
     So what would make this Stone Age culture want to work together in such a way? Well maybe the answer lies in the site itself. The landscape provides a natural axis for midsummer and midwinter sunrise and sunset. This uniqueness is summed up by Professor Parker Pearson, of the University of Sheffield (part of the Riverside Project) "When we stumbled across this extraordinary natural arrangement of the sun's path being marked in the land, we realised that prehistoric people selected this place to build Stonehenge because of its pre-ordained significance". "Perhaps they saw this place as the centre of the world".

Edited from BBC News (22 June 2012)