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Ohio's Magnificent Earthworks, an Ancient Astronomical Wonder

The Newark Earthworks of Ohio showcase ancient astronomical and mathematical precision that is more accurate than that of any surveying instruments of today.

Deep inside the unassuming borders of what is today Ohio sits a complex of earthworks aligned so precisely with the rise and set of the moon that modern surveying equipment could not do better. And this summer, lots of public events means you can enjoy and marvel, as the ancients must have done.

The 2,000-year-old site in what is now Newark, Ohio, is the largest geometric earthworks complex in the world, with approximately 12-foot-high, grass-covered earthen walls outlining huge circles and other forms. Arising gently from its surroundings, the place is both a massive modification of the landscape and a masterpiece of subtlety.

Built two millennia ago, one basket-load of dirt at a time, the biggest enclosures would swallow up several football fields; Stonehenge could be tucked into a tiny corner of one of these gigantic shapes. Newark—along with other Ohio sites Serpent Mound, in Peebles; Fort Ancient, in Lebanon; and Hopewell Culture National Historical Park/Mound City, in Chillicothe—are being considered for UNESCO’s list of World Heritage Sites.

“The Newark Earthworks are proof of our ancestors’ genius,” says Carol Welsh, Sisseton-Wahpeton Oyate and director of the Native American Indian Center of Central Ohio (NAICCO), in Columbus.

What the earthworks’ builders called themselves is not known; archaeologists refer to them as “the Hopewell culture,” after the owner of a farm where artifacts were found during the 19th century. Often people think that mounds always involve burials.

“This is not necessarily so,” says Welsh. “Some did, but most appear to have been places of celebration, where folks came together to pray and honor the gifts of the Earth.”

Many of the summer earthworks events are in and around the Newark site, which has been particularly well studied by mainstream and traditional scientists. In 2006, Ohio State University set up the interdisciplinary Newark Earthworks Center. Its director, history professor Richard Shiels, and program coordinator Marti Chaatsmith, Comanche/Choctaw, encourage both research on the earthworks and community outreach, especially via collaborations with Native people. Find out more at; scroll down and click on “Newark Earthworks Center.”

Bradley Lepper, Ohio Historical Society curator of archaeology, is a prominent authority on the Newark complex, which he has termed a “ceremonial landscape of unprecedented scope.” Community historian and Ohio Archaeology Council member Jeff Gill compares Newark’s multiple celestial alignments and immensely complicated design—melding man-made creations with natural features of the surrounding, hill-ringed river valley—to Egypt’s Valley of the Kings. Astronomer, physicist and Earlham College professor Ray Hively, who worked with Earlham colleague Robert Horn to plot the Newark site’s moonrise and moonset alignments, found that its lunar alignments precisely encode the orb’s very complex cycle, with moonrises and moonsets rotating north and south over an 18.61-year cycle.

Welsh counts that as evidence that the site celebrates female power.

“The 18.61-year period is essentially a generation,” she says. “So the lunar emphasis at Newark and similar places honors women and the cycle of life.”

It’s clear the ancients were virtuosic geometers and astronomers. Lepper describes research on their sophisticated mathematics in a 2010 paper, The Ceremonial Landscape of the Newark Earthworks and the Raccoon Creek Valley. In one of many examples Lepper gives, he notes that the circumference of one of the massive Newark circles is equal to the perimeter of a nearby square. The diameter of another circle appears to have been used as a gigantic measuring stick for laying out the site.

Further, the construction of squares and circles with equal areas solved a primordial math problem—squaring the circle—that fascinated and flummoxed mathematicians as far back as the fifth century B.C. in Ancient Greece. For millennia scholars have considered solving this problem to be so difficult that the phrase “squaring the circle” has come to mean doing the impossible.

Equally astonishing, the geometry and the lunar alignments of the Newark Earthworks appear to coordinate with those in other complexes many miles away, according to Chaatsmith. Lepper has shown that one set of parallel walls exiting the Newark site points directly to the collection of burial mounds now protected as Hopewell Culture National Historical Park, in Chillicothe, 60 miles away. The Newark walls may demark a ceremonial passage to the Chillicothe complex, says Lepper, though centuries of development and agricultural plowing have destroyed much of the evidence needed to prove that.

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Additional parallel-walled pathways in Newark connected the earthworks complex to encircling rivers. If anything like today’s Eastern Woodlands cosmology was operating back then, according to Lepper (and there’s evidence that it was, he says), travelers arriving by canoe may have traversed the walled paths not just physically but also spiritually. As visitors moved from the waterways to the ceremonial site, they made a concurrent voyage through the three layers of their universe—from the “Underwater” or “Beneath World” of the rivers to the “Middle World” of ordinary life and finally to the celestial “Above World” of the ritual place.

Though many of Ohio’s earthworks and mounds have been obscured or taken to the ground by farms and towns, their energy endures. During a recent visit, a hawk—the bird revered by the ancients—surfed the thermals above a mound outside Chillicothe that had been plowed flat. The bird appeared to be standing guard, 2,000 years after the site’s builders had walked on.


Summer in the Earthworks: 2012 Events

This summer one can enjoy the Ohio sites’ magnificence, quiet beauty and sublime meaning during earthworks-themed concerts, lectures, night-sky events, children’s programming and more, throughout the verdant, mostly rural south-central part of the state.

On June 21, Carol Welsh, Sisseton-Wahpeton Oyate and NAICCO director, and her husband, Mark Welsh, Ihanktonwan Dakota/Mohawk, host 5:30 a.m. sunrise and 8 p.m. sunset events at the complex in Newark to herald the summer solstice.

For more opportunities to participate in celebrations in Newark and at other sites, including Serpent Mound and Fort Ancient, go to, and click on “Events.”

“I love being able to share the earthworks with Native and non-Native folks,” says Welsh. “They reinforce the good of being Indian.”

The Earthworks and sister sites will also host some of the observances and ceremonies being held across the country from June 16 through June 24 to mark the 2012 National Days of Prayer to Protect Native American Sacred Places, sponsored by the Morningstar Institute.

Peebles - Serpent Mound, Wednesday, June 20, 10:00 a.m.–9:00 p.m.

Newark - Newark Earthworks, Great Circle entryway, Thursday, June 21, 6:00 a.m./8:00 p.m.

Chillicothe - Hopewell Culture National Historical Park, Mound City, Thursday, June 21, 7:00 p.m.

Oregonia - Fort Ancient Earthworks, Saturday, June 23, 5:30 a.m.