The Serpent Mound Debate

Archaeologists disagree about who built this remarkable effigy mound now known as Serpent Mound, and when they did it.

An aerial photograph of Serpent Mound taken from a drone. The mound is a National Historic Landmark. Credit: Jarrod Burks.
An aerial photograph of Serpent Mound taken from a drone. The mound is a National Historic Landmark. Credit: Jarrod Burks.

Fall 2017: By David Malakoff.

Anyone who has tried to catch a snake knows the reptiles are elusive. So it only seems appropriate that Serpent Mound, a twisting, quarter-mile long, three-foot-high earthwork in southern Ohio, has eluded archaeologists’ grasps for decades. Over the past 170 years, researchers have offered changing and conflicting views on the age of the iconic effigy, which has been designated a National Historic Landmark. Some believe that people of the Adena culture, who created countless elaborate earthen mounds in the central Ohio River Valley and adjacent lands, built the serpent about 2,300 years ago. But others assert that it’s less than half that age, and that it was produced by the Fort Ancient people, who also built earthworks in this region.

Regardless of who is right, recent research has cast new light on one of North America’s most distinctive, mysterious, and disputed ancient sites. “The great Serpent Mound is a really special place,” said archaeologist Bradley Lepper of the nonprofit Ohio History Connection, which owns the site. “You can’t walk along those curves without wanting to know more about who built it, when they built it, and what they were thinking. It is just a fascinating effigy.”

In the 1840s, journalist Ephraim Squier and physician Edwin Davis—both avid artifact collectors—embarked on a systematic effort to document and map ancient earthworks across the Eastern United States. In 1846, acting on a vague tip about a “work of defence” atop a heavily wooded cliff overlooking Brush Creek in Adams County, the two men were surprised to find the giant effigy. After careful mapping (a backbreaking task), its form became clear: an enormous egg-shaped head with a single eye, attached to a body with a half-dozen curves and a tightly coiled tail. It was, they later wrote, “probably the most extraordinary earthwork thus far discovered.” Scholarly speculation about the serpent’s origins began swirling.


Read more about 3D Modeling Ohio Earthworks from our recent blog by Jamie Davis.

Read More in our FALL 2017 Issue of American Archaeology, Vol. 20 No. 4. Browse Content of this Issue: Fall 2017 . Browse Articles Excerpts from our last issue, SUMMER 2017.

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  1. I challenge that it is a serpent at all. Are we to believe that they built an effort to a snake overlooking the river, the river that was their life source? I would re-examine the theory and consider that this is more likely an effigy to the river.


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