Serpent Mound
Also known as: Great Serpent Mound State Memorial
_(cropped).jpg){kind=link}
Why it's listed
Serpent Mound is an earthen effigy on a hilltop spur above Brush Creek near Locust Grove, Ohio. The embankment represents a serpent uncoiling. It follows the curve of the land for 737 feet and measures 1,254 feet along its windings, with seven deep curves, a coiled tail and open jaws reaching toward an oval mound. It stands 4 to 5 feet high and averages 20 feet wide. Nearby are a conical burial mound, a smaller burial mound, an oval mound and a cluster of stone graves and fireplace areas. Squier and Davis described the site in 1848, and Frederic Putnam excavated and restored it after 1886. The conical mound shows Adena traits, which is why the effigy is attributed to the Adena period, roughly 1000 B.C. to 200 A.D. The mound is described as the largest and finest serpent effigy in the United States. Builders outlined it with stone and clay, then covered it with dirt. The purpose of the effigy remains uncertain.
Significance in brief: The nomination calls it one of the few effigy mounds in Ohio and the largest and finest serpent effigy in the United States. Associated mounds and burials point to an Adena date of about 1000 B.C. to 200 A.D. Excavations in 1886 yielded information about the effigy's construction and about the lifestyle and burial practices of its builders.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 66000602, listed October 15, 1966. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence medium).
Key facts
| Address | 5 mi. NW of Locust Grove on OH 73, Locust Grove |
|---|---|
| County | Adams County |
| Listed | October 15, 1966 |
| Reference number | 66000602 |
| Resource type | Site |
| Period of significance | approximately 1000 B.C. - 200 A.D. |
| Areas of significance | Prehistoric |
| Level of significance | National |
| National Historic Landmark | Yes, designated July 19, 1964 |
| Status (as stated in the nomination) | Condition marked good and altered, in public ownership and used as a park and museum. Intrusions include an access road, a parking lot and a steel observation tower. A museum, barn, residence, service building and shelter lie within the boundary but are not part of the landmark. |
| Acreage | 60 |
| Coordinates | 39.02466, -83.43071 (NPS GIS) |
What listing means for this property
Sites (archaeological sites, battlefields, landscapes) are often listed with a restricted address to protect them from looting or disturbance. Listing is honorary for private owners; federal undertakings on or near the site go through Section 106 review, and state laws may protect burials and artefacts regardless of listing.
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 66000602.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q968802
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.