(CNN) Five thousand years after the construction of Stonehenge, archaeologists finally identified exactly where the blue stones that form part of the imposing UK monument came from and how they were unearthed.
The researchers revealed in 2019 the the stones came from an old quarry on the north side of the Preseli hills in western Wales, which means that the 43 huge blue stones were moved an impressive distance of 150 miles.
Now, archaeologists say they believe that some of the blue stones first formed another circle of stones near the same quarry area and were dismantled and rebuilt as part of Stonehenge on the Salisbury Plain.
The identical 110-meter diameters of the stone circle, known as Waun Mawn, and the Stonehenge ditch, suggest that at least part of the circle was brought from its location in Wales for Salisbury Plain, according to new research published in the journal Antiquity.
This stone hole was discovered at Waun Mawn, with the stone packaging used to protect the missing monolith still present.
Furthermore, the two stone circles are aligned at the sunrise of the summer solstice, and one of the blue stones at Stonehenge has an unusual cross section that corresponds to one of the holes left at Waun Mawn, the newspaper said.
The chips in that hole are the same type of rock as Stonehenge stone, he added.
Revealing stone holes
Stonehenge is made up of two types of stone: larger sarsen stones and smaller bluestone monoliths.
About 43 blue stones survive today at Stonehenge, although many of them remain buried under the grass.
They were considered the first to be erected at Stonehenge 5,000 years ago, centuries before the largest sarsen stones were brought just 15 miles from the monument.
The Stones of Stonehenge research project is led by Mike Parker Pearson, a professor at University College London.
The discovery of the dismantled stone circle at Waun Mawn came by trial and error, the statement said.
Only four stones were visible on the site. In 2010, they were thought to be part of a circle of stones, but the initial geophysical studies were inconclusive and the team decided to focus their energies elsewhere.
The excavation of the stone holes at Waun Mawn revealed the scale of the monument.
An experimental excavation at the site in 2017 found two empty stone holes, but ground radar searches have yet to be successful, leaving the team with no choice but to do it the old way and dig.
Excavations in 2018 revealed empty stone holes, confirming that the remaining four stones were part of an ancient circle.
Dating of coal and sediment in the holes found: the Waun Mawn stone circle was erected around 3400 BC, the study said.
The newspaper also suggested that the stones may have been moved as people migrated from that part of the Wales, with the first person to be buried at Stonehenge, has probably lived in this region.
“My guess is that Waun Mawn was not the only stone circle that contributed to Stonehenge,” Parker Pearson said in a press release.
“Perhaps there is more in Preseli waiting to be found. Who knows? Someone will be lucky enough to find them.”