Field Notes Ohio

Ohio's parks, forests and wildlife areas with camping, the ancient mounds beside them, and the Buckeye Trail that links them. Stories, trails, wildlife, and where to eat and fuel up nearby. Book campsites on ReserveOhio.
Try:
The Buckeye TrailA 1,444-mile blue-blazed loop around Ohio, with all 26 sections.
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Mounds & Earthworks43 ancient sites, including the Great Serpent Mound and the Newark Earthworks.
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Historic Sites39 places, from Fort Steuben and Zoar to Camp Chase and the Rankin House, from the frontier to the Civil War.
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Road Trips33 drives, from the Lincoln Highway to the Morgan Heritage Trail.
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Lake Erie Beaches20 public beaches from Conneaut to Toledo and the islands, with a map.
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Oddities & Roadside Attractions19 giants, ghosts and folk-art stops, plus a Mothman just over the line.
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Caves & Caverns12 show caverns, recess caves and rock shelters, with a map.
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Waterfalls34 falls from the Cuyahoga Valley to the Hocking Hills, with trail notes and a map.
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Explore Ohio

One map for every park, mound, historic site, beach, cave, waterfall and oddity in the app.

Lake ErieWest Virginia27 places277 places77 places73 places35 places519 places1913 places1319 places1916 places168 places810 places1010 places109 places98 places820 places204 places43 places3Barkcamp State Park4 places47 places77 places76 places69 places917 places173 places3Harrison Lake State Park2 places2Forked Run State Park3 places32 places26 places610 places103 places32 places2

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117 parks in 7 regions

Newark Earthworks

Newark & Heath · Licking County · Central Ohio
The largest geometric earthworks in the world
UNESCO World Heritage Site (2023)National Historic LandmarkOhio's official prehistoric monument

Visiting information you can trust

Content last reviewed
September 2026 — this is when Field Notes Ohio's content was last checked, not a live status.
Primary official source
Official page
Location confidence
Verified entrance or visitor center
Published coordinates
Check current conditions
Official conditions or closures
Reservations or tickets
Tickets or admission info

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.

Enormous circles, an octagon and a square built about 2,000 years ago, and part of a golf course until 2025.

Parts
Great Circle Earthworks, Octagon Earthworks and Wright Earthworks
Great Circle
A circle about 1,200 feet across with 8-foot walls and a moat, and the bird-shaped Eagle Mound at its center
Octagon
A 50-acre octagon joined to a 20-acre circle, with a 12-foot Observatory Mound
Alignment
The Octagon tracks the moon's rise and set over an 18.6-year cycle
Original size
About 3,000 acres; less than 10 percent survives
Recognition
World Heritage Site in 2023, part of the Hopewell Ceremonial Earthworks

The story

The Newark Earthworks were the largest set of connected geometric enclosures in the world. Built by the Hopewell culture between 100 BCE and 400 CE, they covered about 3,000 acres, and less than a tenth of that survives, in three pieces: the Great Circle, the Octagon and the Wright Earthworks. At the center of the Great Circle sits Eagle Mound, a low mound. The Octagon is a 50-acre octagon with openings at all eight corners, joined to a 20-acre circle by parallel walls, and an Observatory Mound stands in the gateway between them.

In 1982, physicist Ray Hively and philosopher Robert Horn showed that the Octagon encodes the rising and setting of the moon over an 18.6-year cycle. The state named the Newark Earthworks its official prehistoric monument in 2006, and in 2023 the site became part of Ohio's first UNESCO World Heritage Site, the Hopewell Ceremonial Earthworks.

Related sites

The Moon's 18.6-Year Doorway

Every 18.6 years, the moon rises directly through a passageway at the Octagon. The builders laid out eight gateways and walls to mark the extreme moonrises and moonsets of that long lunar cycle, a calendar for a people who watched the sky for decades at a time.

Then, for a century, nobody could walk in. The Ohio militia camped on the Octagon in the late 1800s as Camp McKinley and helped save it. From 1910, the Moundbuilders Country Club leased it as a golf course, and for years visitors saw the moon-marking mounds between the greens and fairways.

Behind the legend

The lease is a documented story. The Ohio Historical Society leased the Octagon to the country club, and a lease that ran into 2078 was finally bought out by the Ohio History Connection, which took control on January 1, 2025 and opened the site to the public daily during daylight hours. The alignment, first described in 1982, is now accepted as a design feature of the Octagon.

The Newark Earthworks, together with Fort Ancient and the Hopewell sites near Chillicothe, make up the eight sites of the Hopewell Ceremonial Earthworks, inscribed by UNESCO in 2023.

If you go

Walk the Octagon, look for the Observatory Mound and imagine the moonrise. Then visit the Great Circle and its museum, and drive to Alligator Mound in Granville.

Visiting

Status
Open daily in daylight
Managed by
Ohio History Connection
Hours
The Octagon Earthworks is open daily during daylight hours, with staff at the visitor center during posted hours. The Great Circle has a museum; check hours.
Admission
Check with the Ohio History Connection.
Please note
Do not climb or walk on the walls.
Official information →Directions

Parks nearby

Buckeye Lake State Park
About 12 miles · Ohio's oldest state park, with a floating bog and a canal-feeder lake.
Open
Dillon State Park
About 20 miles · A lakeside park close to Flint Ridge and Blackhand Gorge.
Open

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