Woodhenge at Cahokia was rebuilt multiple times — at least five different circle configurations have been identified through excavation, representing successive constructions over a period of several centuries.

The rebuildings were not simply replacements of a deteriorating structure; the successive circles were placed in slightly different positions, which may reflect refinements in the astronomical alignments, changes in where the central observation point was located, or possibly changes in the specific dates being marked.

The social and religious significance of this kind of astronomical observation in Mississippian culture is difficult to reconstruct with certainty from archaeological evidence alone.

What can be inferred is that the ability to mark the solar calendar with precision was important enough to justify the construction and periodic reconstruction of a large and carefully engineered monument.