Stone age wall found at bottom of Baltic Sea ‘may be Europe’s oldest megastructure’

A string of boulders almost a kilometre long, now covered by the Baltic Sea, could be Europe’s oldest human-made megastructure. Researchers say the “pristine” discovery was probably used for hunting the Eurasian reindeer more than 10,000 years ago. Before it was submerged by rising sea levels about 8,500 years ago, hunters might have used the wall to force prey into a bottleneck or a nearby lake.