I did happen to run into some additional information on the barrow cemetry, which might be interesting for those who plan to visit the site. If you parked your car at the Riels Hoefke and walk towards the barrows, you will see a difference in height between the moorlands and the little river you have to cross. Although it is only a few meters, the little river clearly forms a shallow valley.
On an old map of 1760 I found that there was a ford where now is a the little bridge. On the east site of the valley you find the barrow-cemetry. They were generally constructed on higher (dry) grounds Therefore they also served as a landmark to lead one to the ford. On the west site of the valley there was also a group of barrows. The have disappeared a long time ago. They also served as a landmark to lead one the ford. The ford has been used since 800 BC. The 5 tracks coming together near the barrow lead to the ford from various directions.
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