One of the stones at Stonehenge in southern England does not come from Wales, as was long thought, but from much further afield: north-east Scotland.

The so-called altar stone is one of the largest stones used to build a megalithic monument. The stone’s name probably goes back to a 17th-century antiquarian who first suggested that the flat stone might have been a prehistoric altar.

The altar stone is a thick, six-ton ​​block that sits in the center of the stone circle, according to new research published in the journal natureThe block was transported 450 miles from north-east Scotland about 5,000 years ago.

The findings disprove a long-held idea that the altar stone originated in Pembrokeshire, Wales. Last year, researchers concluded that the stone could have come from there, but where it came from remains a mystery.

The solution came from an Australian research team, which had access to one of the world’s largest databases of different types of rock. The researchers compared pieces of stone that fell from the altar stone with data from the database and discovered a match with stones from the Orcadian Basin in Scotland.

The origins of the other stones have already been determined earlier. In fact, some are from Wales, others from England. Not a single stone from Scotland has been included.

“This stone has travelled a very long way – at least 700 kilometres – and this is the longest journey of any monument stone of that period,” said Nick Pearce, who co-authored the 2017 paper. nature“That distance was amazing at the time.”

The new information raises new questions, says Robert Exer, who also co-authored the study. “How was the altar stone transported from northern Scotland to Stonehenge, and more interestingly, why?”

Transport by land and sea must have been a huge challenge. “This research has implications for our understanding of Neolithic societies, their interconnections and transport systems,” the researchers said.