Three years ago, a team of geologists discovered a strange row of stones almost a kilometer long at the bottom of the Mecklenburg Gulf, a large bay located in the southwest of the Baltic Sea. The site is 21 meters deep and the approximately 1,500 rocks were aligned so regularly that it seemed impossible that their arrangement was the result of chance.
Now, a group of experts from the universities of Kiel and Rostock and the Leibniz Marine Research Institute have come to the conclusion that Stone Age hunter-gatherers probably built this megastructure to hunt reindeer about 11,000 years ago.
As explained in an article published in the journal Proceedings of the National Academy of Science (PNAS), underwater archaeologists have explored the site and have determined that the structure has stones a few dozen centimeters in diameter and connects several large boulders. .
The wall was built next to an ancient lake or swamp before sea levels rose significantly after the end of the last ice age. Hence, divers collected sediment samples from the nearby basin to date more precisely the period in which it was built.
“Our explorations indicate that it is not very likely that the underwater wall has a natural origin or that it was built in modern times, for example in connection with the laying of underwater cables or rock extraction. The methodical arrangement of the numerous small stones connecting the large immobile boulders runs counter to this,” explains Jacob Geersen, lead author of the study.
At the end of the last ice age, the total population in northern Europe was probably below 5,000 people, specialists say. “One of their main food sources was reindeer herds, which migrated seasonally across the sparsely vegetated post-glacial landscape. "The wall probably served to guide the reindeer towards a bottleneck between the adjacent lake shore and the wall, or even towards the lake, where Stone Age hunters could kill them more easily with their weapons," adds Marcel Bradtmöller. from the University of Rostock.
Similar prehistoric hunting structures had already been found in other parts of the world, for example at the bottom of Lake Huron (Michigan), 30 meters deep, which were used to capture caribou (the North American equivalent of reindeer). Those walls even share many characteristics with those of Mecklenburg.
The last herds of reindeer disappeared from northern Europe about 11,000 years ago, when the climate became warmer and forests spread. That is why the stone wall was most likely not built after that time, which would make this construction the oldest human structure ever discovered in the Baltic Sea.
“Although numerous well-preserved Stone Age archaeological sites are known in Wismar Bay and along the coast of Mecklenburg-Western Pomerania, these are located in much shallower waters and mostly date from the Mesolithic and Neolithic periods. (between 7000 and 2500 BC),” say the researchers.
In the coming months it is planned to analyze the wall and the surrounding seabed in more detail using side scan sonar, sediment echo sounder and multibeam echo sounder devices. “We have evidence of comparable stone sites elsewhere in the Gulf of Mecklenburg, which we will investigate later,” concludes Jens Schneider von Deimling from the University of Kiel.
