Great Serpent Mound

Above left: Squier and Davis's 1848 Ancient Monuments of the Mississippi Valley, plate XXXV.

Adena Culture ancestral site, constructed 321 B.C.E.; located on a plateau of the Serpent Mound crater, a meteorite impact structure, along Ohio Brush Creek several kilometers north of Peebles, Ohio. Serpent Mound is the world's largest serpent effigy mound. Archaeologist have found no burials or artifacts. The head of the serpent is aligned to the summer solstice sunset and the undulations of the coils also may point to the winter solstice sunrise and the equinox sunrise.

Elevation is 233 meters (766 feet) above sea level.

Materials: a layer of yellowish clay and ash , reinforced with a layer of rocks, and covered with a layer of soil.

Data for CG model:
1. Morgan, William N., 1980. Prehistoric Architecture in the Eastern United States, MIT Press, Cambridge, Massachusetts and London, England,
2.Squier and Davis, Ancient Monuments of the Mississippi Valley, Smithsonian Institution Press in 1848
3. Sea, Geoffrey, 2014. History Got It Wrong: Scientists Now Say Serpent Mound As Old as Aristotle,
http://indiancountrytodaymedianetwork.com/2014/08/07/rethinking-ohios-history-serpent-mound-older-some-its-dirt-156268
4.http://ancientearthworksproject.org/1/post/2014/07/new-radiocarbon-dates-suggest-serpent-mound-is-more-than-2000-years-old.html