Field NotesOhio
Upper Falls in the Old Man's Cave gorge, Hocking Hills, with visitors on the rocks

An independent field guide · 365 places

The field guide to outdoor Ohio

Parks and forests, ancient mounds, caves, waterfalls and back roads, with the story behind each place and where to eat and fuel up nearby.
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  • 117parks & forests
  • 64ancient mounds
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Old Man's Cave, Hocking Hills · Photo: Rhododendrites, CC BY-SA 4.0

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Horn Mound

Tarlton · Pickaway County · South-Central Ohio
An undisturbed mound beside a stream near Tarlton
National Register of Historic PlacesVirtually undisturbed

A pristine mound at the end of a country road, guarded by nothing but a creek.

Setting
Along a stream, well away from other prehistoric sites, at the dead end of Armstrong Road southeast of Tarlton
Condition
Virtually undisturbed by human digging, though the nearby stream threatens it with erosion
Believed built by
The Adena culture
Listed
National Register of Historic Places, 1974

The story

Horn Mound stands near the village of Tarlton in eastern Pickaway County, beside a stream and a good distance from any other prehistoric site. It is believed to have been built by the Adena, who made many burial mounds and ceremonial earthworks in prehistoric Ohio. The stream is slowly eating at it, but human exploration has left it virtually undisturbed, and because of its pristine condition it is considered a likely archaeological site. It was listed on the National Register of Historic Places in 1974.

Related sites

Visiting information you can trust

Check before driving — this site is seasonal, approximate, privately run, or otherwise uncertain. Confirm hours and access with the official source above.
Content last reviewed
September 2026 — this is when Field Notes Ohio's content was last checked, not a live status.
Location confidence
Approximate — boundary or exact point not confirmed
Approximate location

Prices, hours, closures, campsite availability and trail conditions shown elsewhere on this page are not live — always confirm with the official source before you go.

The Mound at the End of the Road

Follow Armstrong Road southeast of Tarlton until it dead-ends and the Horn Mound is there, in the open, next to a stream. It is remote, apart from any other ancient site, and it has been left almost entirely alone.

The only thing that threatens it is the creek beside it.

Behind the legend

The details come from the National Register's description: the isolation, the near-pristine state and the risk from erosion. The Adena label rests on the mound's shape and setting, not on any excavation.

Because it sits at a road's end, it can be seen, but it is not a developed visitor site.

If you go

Drive out on Armstrong Road and look from the road end. Treat it as you would a cemetery.

Visiting

Status
Roadside landmark
Managed by
Check locally
Hours
Visible from the dead end of Armstrong Road; confirm access before you go.
Please note
Please respect private property and stay off the mound.

Parks nearby

A.W. Marion State Park
About 14 miles · A small lake park on the Pickaway plains.
Open
Lake Logan State Park
About 13 miles · A quiet lake near Hocking Hills.
Open

Details last checked 2026-09-22. Confirm hours and prices before you go.

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