For ample explanations about the megaliths, in Drenthe and elsewhere, I refer to this post, the first one in this series.
Actually there's one non-hunebed in this post, and that's the D43 at the bottom. That one is a long barrow, a chambered tomb, the only one in The Netherlands.


Hunebed D12 in Eext - One of the smaller dolmens in Drenthe


Detail of Hunebed D20 in Drouwen


Hunebed D26 in Drouwen (in the middle of the pouring rain indeed)


Hunebed D14 in Eext


Hunebed D40 in Emmen


Detail of the long barrow (D43) in Emmen