u/MechanicIcy6832

This gravesite is called "Sundermannsteine" and it's just one of many such neolithic sites in and around Osnabrück. There are over 30 of these sites in northwestern Germany and it's called the "Route of Megalithic Culture". These sites are thought to originate from around 3500-2800 BC and are attributed the so called "Funnel Beaker Culture".