The dutch polders and wetlands are probably the most interesting and peculiar part of the country. When you've some days left during your travels in the Netherlands, hiking some of the polder landscapes is a good option.
The polders in the Netherlands are very, very varied. For you as a hiker, dive into the history of the polders you explore. Try to grasp the way they function.
Parts of the moors and bogs were left wild, because it was too difficult to reclaim the land. Often. the peat was excavated and reclamation didn't work out as planned. The North Sea did it's part in "reclamation" too. The result is a unique pattern of farmlands, waterways, wetlands, constructions.