These are clearly some sort of special purpose facilities or infrastructure. Current evidence strongly indicate that these woodhenges served calendric purposes. Fowler (1996) and Wittry (1996), among others for example, have noted that the alignment of posts within these woodhenges correspond to where the sun rose and/or set on the first days of equinoxes and solstices. The importance of these solar events is underscored by the recovery of numerous unique artifacts at the bases of some posts. One such artifact, a small ceramic pot with a cross-in-circle design, was found in a pit near the winter solstice siting pole.

Beaker found in an offertory pit near the siting post for the winter solstice sunrise.

Fowler's recent work on Mound 72 has been particularly informative. He suggests that the associated woodhenge defined a sacred place on the Cahokia landscape. Mound 72 construction and interrment of high status individuals followed this definition of a sacred space with the woodhenge.