Stonehenge's Continental Cousin
archaeology.org
archaeology.org
At bottom you can see some rectangular structures of three rows of post holes identified as "longhouses", a commonly-identified neolithic building technique.
Given the "ring" is also three rows of posts about 5m apart (with the two inner rings having nearly the same feature count and the outer ring having close to twice the features), it makes me suspicious that this structure (and the many others like it in Britain and northern Europe) was also a building, a (monumental) annular longhouse. Whether shrine, palace, fort, or some combination, a building makes a lot more sense than a bunch of freestanding posts.
For the other sites, see here: https://en.wikipedia.org/wiki/Neolithic_circular_enclosures_...