10 Euros Carnac stones

The Carnac alignments in Brittany represent the largest concentration of megalithic standing stones in the world — over 3,000 stones arranged in parallel rows stretching nearly four kilometers, erected by Neolithic peoples between roughly 4500 and 2000 BC. Their purpose remains genuinely unresolved; astronomical alignment theories compete with ceremonial and territorial explanations, and no consensus has held. This coin is part of Monnaie de Paris's ongoing "Trésors de France" series, which has issued commemoratives tied to French heritage sites since the early 2000s.