December
16
/ 2025
French marine archaeologists have made a groundbreaking discovery off the coast of Brittany - a massive underwater wall dating to approximately 5000 BC that predates the famous megalithic monuments of the region by 500 years. The 120-meter-long granite structure, the largest underwater construction ever found in France, offers stunning new evidence of sophisticated coastal societies that thrived during the Mesolithic-Neolithic transition. The monumental wall was discovered near Île de Sein, a small island at Brittany's western tip, now submerged under nine meters of water. According to a study published in the International Journal of Nautical Archaeology, this extraordinary find challenges previous understanding of early European coastal communities and their engineering capabilities. Archaeologist Yvan Pailler noted that the wall was "built
