The Great Serpent Mound is a 1,348-feet-long (411m), four-feet-high precontact effigy mound located in Peebles, Ohio, United States. It was built on what is known as the Serpent Mound crater plateau, running along the Ohio Brush Creek in Adams County, Ohio. The mound is the largest serpent effigy known in the world. The first published surveys of the mound, by E. G. Squier and Edwin Hamilton Davis, were featured in their 1848 study Ancient Monuments of the Mississippi Valley, commissioned by the Smithsonian Institution.
A serpent on a ridge
Effigy mounds have been constructed independently by several cultures. The significance of Serpent Mound is based on its size and historical relevance. Made up of three parts, Serpent Mound extends over 1,348 ft (411 m) in length, varying from 9 in (23 cm) to more than 3 ft (91 cm) in height. The mound stands with a width varying between 22 and 24 ft (6.7 and 7.3 m) based on the section. Serpent Mound conforms to the surrounding land, as it was built on a bluff above the Ohio Brush Creek.
The mound winds back and forth for more than eight hundred feet, with its tail coiling in seven areas throughout the mound. The mound features a triple-coiled tail at the end of the structure, often viewed as a benchmark of the mound. Yellowish clay and ash make up the main constituents of the mound, with a layer of rocks and soil reinforcing the outer layer. Squier and Davis interpreted the structure as an open-mouth head of a that nearly engulfs an east-facing hollow oval feature and is 120-foot (37 m) long.
Squier and Davis believed the oval feature may represent an egg, with an apparent depiction of the snake consuming it. Archaeologist J.P. McLean identified the mound as the body of a frog. The western side of the effigy features a triangular mound approximately 31.6 ft (9.6 m) at its base and long axis.
Debating the builders and date
Throughout the 20th century, anthropologists and archaeologists disputed whether peoples of the Adena or Fort Ancient archaeological cultures had created the Serpent Mound. In 2014, radiocarbon dating determined the mound was built in 300 BCE by the Adena peoples. This date was corroborated in 2019. Additionally, it was found that the mound was rebuilt or repaired around 1100 CE during the Fort Ancient period. These dates were later challenged by archaeologist Brad Lepper, who published a response questioning the attribution of construction to the Adena culture.
The Adena culture consisted of the pre-contact Native Americans who lived in what would become the states of Kentucky, Indiana, Pennsylvania, West Virginia, and Ohio. The majority of these peoples inhabited the Scioto River and Hocking River valleys in southern Ohio and the Kanawha River Valley near present-day Charleston, West Virginia. This period is often referred to as the Early Woodland period, ranging between 800 BCE and 1 CE. The name "Adena" refers to the shared culture of the peoples rather than to a singular group or tribe.
The Fort Ancient Culture refers to the peoples who predominantly inhabited land near the Ohio River valley in a culture that flourished from 1000 to 1750 CE. These civilizations flourished in the modern-day regions of southern Ohio, northern Kentucky, southeastern Indiana, and western West Virginia. The Fort Ancient tribes are often referred to as a "sister culture" of the Mississippian culture.
Meaning and preservation
Archaeologist Brad Lepper has suggested that Serpent Mound may represent a Dhegihan Siouan origin story involving a Great Serpent of the Beneath World. This is an interpretation rather than a recovered statement from the builders. Astronomical explanations have also been proposed. In 1987, Clark and Marjorie Hardman reported that the oval and head area aligned with the summer solstice sunset, while the coiled tail aligned with the winter solstice sunrise. Such correspondences have contributed to debate about whether parts of the design intentionally marked celestial events.
The three curves of the serpent possibly have alignments to the summer solstice sunrise, equinox, and winter solstice sunrise, or alternatively align with important moonrises in the lunar cycle. However, the lines of sight are too short and vague to determine the actual alignment. Frederic Ward Putnam of the Peabody Museum of Archaeology and Ethnology at Harvard University spent much of his career lecturing and publishing on the Ohio mounds, specifically the Serpent Mound. When he visited the Midwest in 1885, he found that plowing and development were destroying many of the mounds.