Serpent Mound, in Adams County, is the largest documented surviving example of a prehistoric effigy mound in the world. It is a sinuous earthen embankment 411 meters long, including an oval embankment at one end, which has been interpreted variously as the serpent's eye, part of its head, or a secondary object, such as an egg, grasped in the serpent's open jaws. The effigy ranges from 1.2 to 1.5 meters in height and from 6 to 7.6 meters in width. Radiocarbon dates obtained from samples from the effigy, combined with stylistic analyses of the iconography, indicate Serpent Mound was built by the Fort Ancient Culture about the year 1120 CE. This state memorial also preserves three Native American burial mounds as well as evidence of contemporary habitation sites.
Justification de la Valeur Universelle Exceptionelle
This monumental geoglyph embodies fundamental cosmological principles of an indigenous ancient American Indian culture. Serpent Mound represents the acme of prehistoric effigy mound-building in the world and is part of a tradition of effigy mound building among some American Indian cultures of the present Eastern United States. Its remarkably naturalistic quality makes it immediately recognizable as a representation of a serpent, and the form also aligns astronomically to mark the passage of the seasons. The Great Serpent was a source of enormous spiritual power that a widespread pre-Columbian culture could invoke to aid them in hunting and in curing illnesses.
Satements of authenticity and/or integrity
Although Serpent Mound was somewhat degraded by 19th century farming and looting, it has been carefully restored and protected, beginning in 1887. Only limited archeological digging has been carried out and what remains has a high degree of authenticity.
Comparison with other similar properties
Geoglyphs in the form of animal or human effigy mounds, or intaglios, appear around the world. The Lines and Geoglyphs of Nasca and Pampas de Jumana (in Peru) is the only such site currently inscribed on the World Heritage List. Other examples include the Uffington Horse (UK), the Cerne Abbas Giant (UK), the Serpent Mound at Loch Nell (UK), the Serpent Mound at Rice Lake (California), Effigy Mounds National Monument (Iowa), and the Blythe Intaglios (California). The scale of Serpent Mound dwarfs all other securely documented effigy mounds and is larger than most of the geoglyphs in the world.