The land surface of the valley is slightly undulating due to the presence of coversand ridges. In the Weichselian (115.000 – 11.800 BP), the most recent ice age, the climate was cold, dry and windy, but the Netherlands was not covered with ice. The landscape was open and there was little vegetation, and the surface and soils became frozen (permafrost). The strong, dominantly westerly winds, deflated the fluvioglacial deposits in the braided river beds and former North Sea area, and the blown-out sand was deposited over the older landscape like a blanket. The coversand landscape is marked by the presence of many parabolic dunes that generally have a west-east orientation. The following figure shows the many coversand ridges (parabolic dunes) in the Gelderse Vallei. Coversand was never deposited on top of the push moraines (too windy on top of a hill or mountain!; coversand was always deposited in the lower parts, like the Gelderse Vallei.
Many coversand ridges in the Gelderse Vallei. The second figure below shows an elevation map of the Kraats. The location where you are now standing is indicated by an arrow. You are in fact standing on a parabolic dune, slightly higher than the surroundings.
De Kraats indicated on the elevation map (https://www.ahn.nl/ahn-viewer). The shape of a parabolic dune is clearly visible.