London, September 22 : An excavation inside the Stonehenge has pinpointed the construction of the ancient site to 2300 BC, which is a key step to discovering how and why the mysterious temple was built.
For centuries, archaeologists have marvelled at the construction of Stonehenge, which lies on Salisbury Plain, Wiltshire.
According to a report by BBC News, the origin date for the site was decided by radiocarbon dating, and is said to be the most accurate yet.
The dating is the major finding from an excavation inside the Stonehenge by Professors Tim Darvill and Geoff Wainwright.
The duo found evidence suggesting Stonehenge was a centre of healing.
Others have argued that the monument was a shrine to worship ancestors, or a calendar to mark the solstices.
Estimating the origin date also means that the ring's original bluestones were put up 300 years later than previously thought.
Mineral analysis indicates that the original circle of bluestones was transported to the plain from a site 240km (150 miles) away, in the Preseli hills, South Wales.
This extraordinary feat suggests the stones were thought to harbour great powers.
Professors Darvill and Wainwright believe that Stonehenge was a centre of healing - a "Neolithic Lourdes", to which the sick and injured travelled from far and wide, to be healed by the powers of the bluestones.
They note that "an abnormal number" of the corpses found in tombs nearby Stonehenge display signs of serious physical injury and disease.
The analysis of teeth recovered from graves show that "around half" of the corpses were from people who were "not native to the Stonehenge area".
"Stonehenge would attract not only people who were unwell, but people who were capable of healing them," said Professor Darvill, of Bournemouth University.
But without a reliable carbon date for the construction of Stonehenge, it has been difficult to establish this, or any other, theory.
Until now, the consensus view for the date of the first stone circle was anywhere between 2600 BC and 2400 BC.
To cement the date once and for all, Professors Darvill and Wainwright were granted permission by English Heritage to excavate a patch of earth just 2.5m x 3.5m, in between the two circles of giant sarsen stones.
The dig unearthed about 100 pieces of organic material from the original bluestone sockets, now buried under the monument. Of these, 14 were selected to be sent for modern carbon dating, at Oxford University.
The result - 2300 BC - is the most reliable date yet for the erection of the first bluestones.
Strictly speaking, the result was rounded down to "between 2400 BC and 2200 BC" - but 2300 BC is taken as the average.