The Great Serpent Mound is a 1348 feet (410.9 m)-long, three-foot-high prehistoric effigy mound

Effigy mound

Sites in the U.S. of similar history may be found at Indian Mounds ParkAn effigy mound is a raised pile of earth built in the shape of a stylized animal, symbol, religious figure, or human figure. Effigy mounds were only built during the Late Woodland Period .Effigy mounds were constructed in many...

 located on a plateau of the Serpent Mound crater

Serpent Mound crater

Serpent Mound crater, also known as the Serpent Mound Disturbance, is an eroded meteorite impact crater in Ohio, United States. It lies largely in Adams County, with the northern part mostly in Highland County, except for a small northeast part in Pike County.It is classified as a complex crater...

 along Ohio Brush Creek

Ohio Brush Creek

Ohio Brush Creek is a tributary of the Ohio River in southern Ohio in the United States. Via the Ohio River, it is part of the watershed of the Mississippi River, draining an area of...

 in Adams County, Ohio

Adams County, Ohio

As of the census of 2000, there were 27,330 people, 10,501 households, and 7,613 families residing in the county. The population density was 47 people per square mile . There were 11,822 housing units at an average density of 20 per square mile...

. Maintained within a park by the Ohio Historical Society, it has been designated a National Historic Landmark

National Historic Landmark

A National Historic Landmark is a building, site, structure, object, or district, that is officially recognized by the United States government for its historical significance...

 by the United States Department of Interior. The Serpent Mound of Ohio was first reported from surveys by Ephraim Squire and Edwin Davis in their historic volume Ancient Monuments of the Mississippi Valley, published in 1848 by the newly founded Smithsonian Museum.

Researchers have attributed construction of the mound to three different prehistoric indigenous

Indigenous peoples of the Americas

The indigenous peoples of the Americas are the pre-Columbian inhabitants of North and South America, their descendants and other ethnic groups who are identified with those peoples. Indigenous peoples are known in Canada as Aboriginal peoples, and in the United States as Native Americans...

 cultures.