Before Stonehenge
Along the coast of Brittany in France, spanning for 4km and standing in perfect alignment, are 3000 towering granite stones keeping guard.
The Carnac Alignment was built by a Neolithic community 6,000 ago (1,000 years before Stonehenge) but no one knows why.
https://www.bbc.com/travel/article/20220914-carnac-alignments-brittanys-mysterious-standing-stones#