It has alwaysbeen a mystery whybluestones, the smallerstones that form part of the circle, were transported around 155 miles from PreseliHills in Wales to Wiltshirein southernEngland.
Over the last six years, the professors have concentrated their research on Carn Menyn - a lonely and atmospheric spot in Pembrokeshire's Preselihills.
They believe that the bluestones, which were transported 250km (150 miles) from the PreseliHills in Wales to the Salisbury Plain in Wiltshire, were brought to the site because the ancient people believed they had healing properties.