https://www.sci.news/archaeology/stone-age-hunting-megastructure-baltic-sea-12687.html

A team of archaeologists from Germany has
discovered a submerged Stone Age
megastructure in the Western Baltic Sea
at a water depth of about 21 m. The
structure was likely constructed by
hunter-gatherer groups more than 10,000
years ago and ultimately drowned around
8,500 years ago; since then, it remained
hidden at the seafloor, leading to a
pristine preservation that will inspire
research on the lifestyle and territorial
development in the larger area.
....
The stonewall is made of 1,673 individual
stones which are usually less than 1 m in
height, placed side by side over a distance
of 971 m in a way that argues against a
natural origin by glacial transport or ice
push ridges.

Dubbed Blinkerwall, it was built by
hunter-gatherers that roamed the region
after the retreat of the Weichselian Ice
Sheet.

Running adjacent to the sunken shoreline
of a paleolake (or bog), whose youngest
phase was dated to 9,143 years ago, the
structure was likely used for hunting
the Eurasian reindeer (Rangifer tarandus).

“At the time, the entire population across
northern Europe was likely below 5,000
people,” said Dr. Marcel Bradtmöller, a
researcher at the University of Rostock.

“One of their main food sources were herds
of reindeer, which migrated seasonally
through the sparsely vegetated post-glacial
landscape.”

“The wall was probably used to guide the
reindeer into a bottleneck between the
adjacent lakeshore and the wall, or even
into the lake, where the Stone Age hunters
could kill them more easily with their
weapons.”
....

https://www.pnas.org/doi/10.1073/pnas.2312008121

https://www.pnas.org/doi/epdf/10.1073/pnas.2312008121
A submerged Stone Age hunting architecture
from the Western Baltic Sea

Significance
Structures from the Stone Age can provide
unique insights into Late Glacial and
Mesolithic cultures around the Baltic Sea.
Such structures, however, usually did not
survive within the densely populated
Central European subcontinent. Here, we
explore a Stone Age megastructure, that
has preserved under water in the Western
Baltic Sea. It was likely constructed by
hunter–gatherer groups more than 10000 y
ago and ultimately drowned during the
Littorina transgression at 8500 y B.P.
Since then, it remained hidden at the
seafloor, leading to a pristine
preservation that will inspire research
on the lifestyle and territorial
development in the larger area.

Abstract
The Baltic Sea basins, some of which only
submerged in the mid-Holocene, preserve
Stone Age structures that did not survive
on land. Yet, the discovery of these
features is challenging and requires
cross-disciplinary approaches between
archeology and marine geosciences. Here,
we combine shipborne and
autonomousunderwater vehicle
hydroacoustic data with up to a centimeter
range resolution, sedimentological samples,
and optical images to explore a Stone Age
megastructure located in 21 m water depth
in the Bay of Mecklenburg, Germany. The
structure is made of 1,673 individual
stones which are usually less than 1 m in
height, placed side by side over a distance
of 971 m in a way that argues against a
natural origin by glacial transport or ice
push ridges. Running adjacent to the sunken
shoreline of a paleolake (or bog), whose
youngest phase was dated to 9,143 ±36 ka
B.P., the stonewall was likely used for
hunting the Eurasian reindeer (Rangifer
tarandus) during the Younger Dryas or early
Pre-Boreal. It was built by hunter–gatherer
groups that roamed the region after the
retreat of the Weichselian Ice Sheet.
Comparable Stone Age megastructures have
become known worldwide in recent times but
are almost unknown in Europe. The site
represents one of the oldest documented
man-made hunting structures on Earth, and
ranges among the largest known Stone Age
structure in Europe. It will become
important for understanding subsistence
strategies, mobility patterns, and inspire
discussions concerning the territorial
development in the Western Baltic Sea
region.