Prehistoric Woodhenge at Cahokia Mounds

Four times a year people gather to mark the change of the season at a circle of log poles erected at Cahokia Mounds State Historic Site. An interpreter explains the importance of the 410-foot diameter structure, dubbed Woodhenge, to Cahokia's agriculture-based society of 1,000 years ago.

Located at Collinsville in Southern Illinois, and only a few minutes drive from the Gateway Arch in St. Louis -- easily visible from atop the 100-foot-tall Monk's Mound from which the Great Sun ruled -- Cahokia Mounds was the largest city in prehistoric North America with a population of up to 20,000.  It had a population so large that it was not surpassed in the United States until sometime in the early 19th Century.

Cahokia's Citizens

No one knows what the original inhabitants called themselves. They were dubbed Cahokia after the local tribe that occupied the region by the French Jesuit explorers who entered the region in the 16th Century, long after the mound-building culture had largely disappeared.

Today, anthropologists refer to them as members of the Mississippian culture.

Native Americans had their own legends about the original inhabitants but no actual knowledge of the the mounds or mound-builders, although, apparently, remnants of the mound-building culture continued among the Natchez encountered by the French further south in the Mississippi River valley.

Woodhenge

Woodhenge as it stands today is merely a reconstruction of the third (ca. 1000 AD) of a series of woodhenge circles that have been located. Although the change of season is noted with a small sunrise ceremony at the solstices and equinoxes, site interpreters keep clear of any religious connotations, although a lone visitor may find a small colorful medicine bag has been poked into a crevice in the wood of the center pole.

Dr. William Wittry discovered the first remains of post pits in the early 1960's. Eventualy, it was determined there may have been as many as five woodhenge circles over time at the site.

Wittry theorized that the posts helped the priests make astronomical sightings so they could perfect their calendars.  Accurate calendars were critical to growing crops sufficient to sustain the (by the standards of the day) huge city.  The city relied on maize as its primary crop, merely supplemented by other crops like squash and lamb's quarters and occasionally fish and meat.  Some experts feel the population growth reached a critical mass and the city's food production system was overloaded, leading to Cahokia's decline and eventual disappearmance.
The circles were maintained between 900-1100 AD. The posts were of red cedar and there is evidence that the posts may have been painted red, a sacred color. There were 24 posts in the first circle constructed, 36 in the second, and in the third, 60 posts. The last circle has only 12 or 13 posts, perhaps because cedar was in short supply.

Two posts each mark the first days of winter and summer and one marks both the first day of spring and of fall. The function of the remaining posts is unclear although there is plenty of speculation. Some may have marked special festival days, others the position of important stars or the moon, the posts may have assisted in establishing locations for proposed mounds, or it may have been that the complete circle served as a symbol.

The center pole in the circle may have held a platform for the sun priest perch on to make his sightings.

Visiting Cahokia

Visitors to the site will find plenty of parking space, certain special events scheduled throughout the year to illuminate Cahokia's past. a visitor's center which offers a movie, a diorama of a view of Cahokia homelife, and numerous displays offering details on how the Cahokians lived from their corn diet to artifacts found by scientists. Archeological digs are underway at Cahokia Mounds and people can tour the digs or even sign up to participate in the digs.

Details on Cahokia Mounds State Historic Site, with maps, directions, events calendar (including dates of equinoxes and solstices), can be found at the website at http://www.cahokiamounds.com/.