These rocks are part of the 'Teufelsmauer' (Devil's Wall). A geologic formation northeast of the Harz mountains. It is several miles long and looks like ruins of a gigant wall. Local legends say there was a bet betwen god and devil. The devil was allowed to keep all land which he could surround by a wall within one day. The devil was too greedy and did not finish his work in time. So he got no country on the surface and what you can see now are remains of this partially finished wall.