Britain’s stone circles really were ancient astronomies say archaeologists who believe they have cracked a mystery that has enthralled visitors to historic sites for years.
Hundreds of stone circles are dotted around the country, and theories about how and why they were built have abounded.
Now, a team of archaeologists headed by Dr Gail Higginbottom of the University of Adelaide, Australia, believe they have the answer to the riddle.
They looked at the alignment of stones placed in two of the oldest stone circles – Callanish Stones on the Isle of Lewis in Scotland and the Standing Stones of Stenness on the Isle of Orkney.
Both were built close to 5,000 years ago and both have stones aligned to the orbits of the moon and sun.
Stones align with sun and moon
The team scrutinised Ordnance Survey maps and compared them to astronomical data and realised that although archaeologists had looked at the sites in detail, they had not investigated how and why the sites had changed over thousands of years.
“It’s the first time individual circles have been assessed to really know what’s going on,” said Higginbottom.
“People have done statistical work on standing stones, but usually as a group. They hadn’t separated them by specific age or by looking at every single line-up in a circle.”
Her study clearly shows that different stones align with the orbits of the moon and sun at different stages of their cycles.
She believes that knowledge of the skies collected by generations of ancient Britons was combined to build the circles with precision to mark astronomical events.
For example, both the Scottish circles have a stone that marks the position of the moon in the north that occurs only once in every 19 years.
Higginbottom also argues the circles were also giant seasonal clocks that helped ancient peoples pinpoint the time of year.
“Around the winter solstice, as the sun was moving further south, and it was getting darker and the days were getting shorter, if they couldn’t confirm that the sun was starting to move north again, towards warmer weather, that would be catastrophic,” she said.