Serpent Mound crater, also known as the Serpent Mound Disturbance, is an eroded meteorite

Meteorite

A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...

 impact crater

Impact crater

In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...

 in Ohio

Ohio

Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...

, United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It lies largely in Adams County

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...

, with the northern part mostly in Highland County

Highland County, Ohio

As of the census of 2000, there were 40,875 people, 15,587 households, and 11,394 families residing in the county. The population density was 74 people per square mile . There were 17,583 housing units at an average density of 32 per square mile...

, except for a small northeast part in Pike County

Pike County, Ohio

As of the census of 2000, there were 27,695 people, 10,444 households, and 7,665 families residing in the county. The population density was 63 people per square mile . There were 11,602 housing units at an average density of 26 per square mile...

.

It is classified as a complex crater because it features a central uplift, a transition zone, and a ring graben

Graben

In geology, a graben is a depressed block of land bordered by parallel faults. Graben is German for ditch. Graben is used for both the singular and plural....

 (a ring-shaped trough in the outer part of the crater). Although eroded, the original rim diameter is estimated at 8 km (5 mi) and the age is estimated to be less than 320 million years (Mississippian or younger).

The crater is named after the Serpent Mound

Serpent Mound

The Great Serpent Mound is a -long, three-foot-high prehistoric effigy mound located on a plateau of the Serpent Mound crater along Ohio Brush Creek in Adams County, Ohio. Maintained within a park by the Ohio Historical Society, it has been designated a National Historic Landmark by the United...

, an 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 in Brush Creek Valley within the crater.