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Writer's pictureDan Wagner

Exploring Ohio's Newark Earthworks: A UNESCO World Heritage Site

Nestled within the serene landscapes of Newark and Heath, Ohio, lies a living testament to the ancient marvels of North America - a complex that beckons explorers and archaeologists to decode the mysteries of the past. Newark Earthworks, the largest set of geometric earthen enclosures in the world, tells a story of the Hopewell culture, a mystifying civilization that thrived in the region over two millennia ago. Spread over four square miles, Newark Earthworks is composed of four colossal sites: the Great Circle Earthworks, the Octagon Earthworks, the Cherry Valley Ellipse, and Wright Earthworks, all interconnected by parallel walls and earthen embankments. Constructed for ceremonial rituals, social congregations, religious observations, and honoring the dead, the complex also bore astronomical importance by facilitating the precise tracking of astronomical events, including the 18.6-year cycle of the moon's orbit. Today, the complex showcases the remarkable scientific acumen of the Hopewell, enduring as a lasting testament to the ancestral heritage of America's ancient civilizations. The complex is so culturally significant that it, along with Fort Ancient Earthworks and the five sites associated with Hopewell Culture National Historical Park, were officially inscribed on the UNESCO World Heritage List on September 19, 2023 as the Hopewell Ceremonial Earthworks, further cementing their status on the world stage.


Newark Earthworks

A Brief History of the Hopewell Culture

Before visiting Newark Earthworks, it is helpful to familiarize yourself with the identity of the Hopewell people, their customs, and the historical significance that surrounds them.


The Hopewell culture was not a single tribe, rather a vast network of prehistoric Native American societies that thrived in parts of eastern North America from 100 BC to 500 AD, during what is known as the Middle Woodland period. The primarily hunter-gatherer civilization was renowned for its extensive trade networks, sophisticated artistry, and large-scale earthworks. They were primarily centered in the region around the Ohio River Valley, but had a widespread influence across a vast area that included parts of present-day Illinois, Indiana, Kentucky, Michigan, Wisconsin, and as far south as the Gulf Coast and Florida.


Well-known for their expansive trade networks covering thousands of miles, the Hopewell engaged in the exchange of precious resources like copper, mica, shells, obsidian and other exotic materials across far-reaching distances. Archaeological evidence confirms this, as artifacts like obsidian spearheads from Wyoming and various copper items from Lake Superior have been unearthed at archaeological sites in southern Ohio.


The legacy of the Hopewell culture is best exemplified by its monumental earthworks and predominantly conical shaped mounds, which served various purposes as burial sites, ceremonial centers, and markers for celestial events. Their architectural achievements were awe-inspiring, with many of the structures ranking among the largest non-fortification or defensive structures in the world. For perspective, a single Hopewell earthwork could contain the Great Pyramid of Giza, once the largest man-made structure in the world, and another could accommodate four structures the size of the Colosseum of Rome.


The Hopewell demonstrated remarkable proficiency in mathematics. Early archaeological studies have revealed compelling evidence that multiple earthworks exhibit striking similarities in their measurements. Notably, the enclosure walls of five square-shaped earthworks, scattered across southern Ohio and located dozens of miles apart, all precisely measure 1,080 feet in length. Additionally, at three other sites, evidence points to nearly perfect circle enclosure walls, each measuring exactly 1,054 feet in diameter, further exemplifying their advanced mathematical knowledge.


Their expertise extended beyond geometry, as they showcased a sophisticated understanding of astronomy within their earthworks. A prime illustration of this can be found in the octagon and circle combinations at two distinct complexes. These earthworks feature precise alignments to key points on the horizon where the moon rises and sets during its 18.6-year-long cycle. The discovery of this celestial cycle indicates that Hopewell sky-watchers engaged in systematic observations of the moon for several generations, demonstrating their profound knowledge and dedication to studying the cosmos.


Around 500 AD, the Hopewell culture experienced a notable decline, marked by the cessation of trade, earthwork, and mound construction, as well as the discontinuation of their characteristic art forms. The specific reasons behind this decline remain a mystery, but archaeologists have explored possibilities such as changes in trade patterns, shifts in the environment, and social transformations as potential contributing factors.


What the Hopewell called themselves and what language they spoke is unknown. Like many ancient civilizations, evidence of their written language, if in fact there was one, has yet to be discovered. Similar to many newly unearthed civilizations, the Hopewell culture got its name from the location where its artifacts were first discovered. Therefore, it was named after the field, once owned by Mordecai Cloud Hopewell in the 1800s, where the first evidence of their ancient culture was found and where the Hopewell Mound Group in Hopewell Culture National Historical Park stands today.


Map of Newark Earthworks

In the mid-nineteenth century, American archaeologists Ephraim Squier and Edwin Davis conducted surveys for the Smithsonian Institution, identifying hundreds of ancient Native American monuments throughout the region. Their comprehensive work, conducted between 1837-1847, culminated in the publication "Ancient Monuments of the Mississippi Valley" by the emerging Smithsonian Institution. During that period, Squier and Davis meticulously created the detailed sketch depicted below, illustrating the complex as they observed it.


Newark Earthworks map

The remarkable sites - Octagon Earthworks (red), Great Circle (yellow), the Cherry Valley Ellipse (green), and Wright Earthworks (blue) - were all linked by substantial parallel walls and causeways at the time of their surveys. Regrettably, today, only 10% of the earthworks originally documented by Squier and Davis have endured. Factors such as agriculture activities, the construction of the Ohio Canal, and the growth of the city of Newark have led to near total obliteration of many of the Hopewell's centuries-long efforts. The Cherry Valley Ellipse has completely vanished from sight and only a small fragment of Wright Earthworks remains today. However, two of the original works, the Octagon Earthworks and Great Circle Earthworks, remain well-preserved, helping visitors grasp the unbelievable scope, beauty, and precision of the Hopewell's monumental endeavors.


Great Circle Earthworks

455 Hebron Rd

Heath, Ohio


Spanning an impressive 1,200-feet in diameter, the Great Circle stands as one of the most substantial circular earthworks in the Americas. Encircling the massive site is a five-foot-deep moat surrounded by eight-foot-high earthen walls. Aside from a single entrance, located along the northeast, the Great Circle remains unbroken. The site is believed to have served as a place for social gatherings and ceremonial rituals by the Hopewell. Over the course of many generations, the Hopewell painstakingly built the site with rudimentary tools crafted from sticks, deer bones, and clam shells. They managed to move an estimated 70,000 tons or 7 million cubic feet of earth, relying solely on woven baskets that could carry no more than 35-40 pounds of earth per load.


Newark Earthworks

Today's archaeologists believe that the inner moat of the Great Circle may have been intentionally created to retain water, similar to how ancient ditches and ponds like those at Fort Ancient Earthworks continue to do so. Another theory suggests that the Hopewell created the moat to serve as a spiritual barrier to the Beneath World, a watery realm described in some Native American traditions.


During a 1920s archaeological survey, compelling proof of the site's ceremonial use emerged. Near the center of the Great circle, researchers excavated three low lying earthen mounds and revealed the remains of a rectangular wooden structure flanked by two interconnected walls. The structure contained a central fire-basin, perhaps used for burning human remains, as well as copper ornaments and fragments of cut mica, all recognized as common elements used in Hopewell ceremonies.


Newark Earthworks

At some point in the past, after the Hopewell had concluded their use of the ceremonial structure, they interred it along with the decorative copper and cut mica fragments beneath three mounds. Unintentionally or not, this burial gave rise to a mound formation that strikingly resembles a bird-like effigy mound, with its head precisely oriented towards the entrance of the Great Circle. Today, we know this central mound grouping as Eagle Mound.


Newark Earthworks

The mound is exceptionally large. Laying beside it gives a sense of scale to it.


Newark Earthworks

An article printed in the Crestline Advocate on July 22, 1887, detailed the Newark Earthworks, including the mound.


Newark Earthworks newspaper article

Another article, circulated by the Daily Ohio Statesman on November 27, 1866 offered its readers another perspective on the earthworks.


Newark Earthworks newspaper article

As previously noted, the Great Circle Earthworks, the Octagon Earthworks, the Cherry Valley Ellipse, and Wright Earthworks were originally linked by extensive earthen embankments spanning several miles, functioning as passageways between the sites. These walls were documented by Squier and Davis and are depicted on the map above. Sadly, the majority of these walls have gradually disappeared with the passage of time. Nevertheless, two resilient examples can still be observed just outside the entrance to the Great Circle. In the photo below, you'll find one of these walls in the bottom-left corner, running parallel to the left edge.


Newark Earthworks

In more recent times, the Great Circle has played a versatile role in local affairs. It served as a training ground during the Civil War, a setting for Buffalo Bill Cody's Wild West Show, and even hosted the 1874 Grand Reunion, where soldiers and sailors from Ohio who has served in the Union Army during the Civil War gathered. This significant event drew the attendance of notable figures, including then President Rutherford B Hayes, future president James A Garfield, and Civil War General William Tecumseh Sherman.


Visitors have the freedom to explore the site, but it's important to note that walking on the mounds, walls, and in the moat are not allowed. There is a small museum located near the entrance of the Great Circle, although its operating hours are not particularly convenient. There is no fee to enter the site.


Octagon Earthworks

125 N 33rd St

Newark, Ohio


A few miles from the Great Circle, is the meticulously designed Octagon Earthworks. It consists of a 50-acre octagonal enclosure connected to a 20-acre circular embankment by parallel earthen walls. The Octagon itself has eight walls, each measuring approximately 550 feet in length and standing about five to six feet tall. The circular embankment walls are roughly the same height and remain largely unbroken.


Newark Earthworks

One of the most intriguing aspects of the Octagon Earthworks is its alignment with celestial events, particularly the moon's movements. Researchers have found evidence that the site was designed to track the lunar cycles, particularly northernmost and southernmost moonrises and moonsets, over the moon's 18.6-year cycle. Within this cycle, there are eight pivotal moments, each illustrated in the graphic below.


Newark Earthworks lunar markings

The Hopewell recognized that on a monthly basis, the location on the horizon where the moon initially appears shifts southward for approximately 14 nights before reversing course. Additionally, they determined that the extent of this movement, between the first and 14th night, expands for 9.3 years and then gradually contracts until it returns to its original position, completing the 18.6-year cycle. The astute Hopewell pinpointed four critical "standstill" moments during the moon's rising trajectory, marking the points where it seemed to pause and change direction: the moon's northernmost and southernmost risings, as well as its northern and southern minimums. They also observed and marked four more instances: the northernmost and southernmost moonset, as well as the northern and southern minimum moonset.


Newark Earthworks

Arguably the most remarkable feature of the Octagon Earthworks relates to the northernmost moonrise. Employing Observatory Mound, in conjunction with the parallel walls connecting the circle to the octagon, and a gateway between two octagon walls, the Hopewell accurately designated the northernmost extent of the moon's path, achieving precision within a mere half-degree. Modern day research has revealed that the Hopewell's precision surpassed that of the builders of England's Stonehenge, being twice as accurate.


Newark Earthworks lunar marking

In the early 20th century, the land where the Hopewell constructed the earthworks 2,000 years ago was transformed into a private country club. While the earthworks remained relatively undisturbed, a legal dispute regarding property rights has arisen between the Ohio History Connection and Moundbuilders Country Club. With the inscription onto the UNESCO World Heritage List, it's likely that the country club will cease to exist in the near future.


Newark Earthworks

Accessing the Octagon Earthworks can be somewhat difficult at the moment. There is an observation platform and a path leading to Observation Mound from the golf course clubhouse and a few interpretive signs beside the parking lot. However, aside from these features, access is restricted to club members.


Wright Earthworks

136 James St

Newark, Ohio


The often overlooked Wright Earthworks consist of a portion of what was once a nearly perfect square enclosure, along with sets of parallel embankments that extended to the Great Circle, the Octagon, and the Cherry Valley Ellipse. Originally, the sides of the complex each measured 940 to 950 feet in length, encompassing a total area of 20 acres. Due to agriculture, the construction of the Ohio Canal, and city development, only 200 feet remain today.


Newark Earthworks

Two thousand years ago, as the Hopewell journeyed between various sites like the Great Circle, Octagon, or Cherry Valley Ellipse, their path inevitably led them through Wright Earthworks, suggesting that this site held a distinct and meaningful significance. When the site was originally constructed, the square was adorned with eight small conical mounds within its perimeter, yet any remnant of these mounds has disappeared over time.


Cherry Valley Ellipse

No longer visible/no address


To the northeast of Wright Earthworks once stood the Cherry Valley Ellipse, a substantial elliptical earthwork that appeared to have held significant importance to the Hopewell people. This site served as the final resting place for many of the builders of the Newark Earthworks and was likely as impressive as the Mound City Group in Chillicothe, Ohio's Hopewell Culture National Historical Park. Originally, the site featured no less than eleven conical burial mounds, along with an irregular shaped mound referred to as Cherry Valley Mound, measuring 140 feet long, 52 feet wide, and 20 feet high, situated at its center.

Newark Earthworks Shaman

Regrettably, a significant portion of the 50-acre Cherry Valley Ellipse was obliterated during the 1820s when the Ohio Canal was being dug and later during the 1850s when the Central Ohio Railroad was constructed. What little remained was subsequently lost to agricultural activities and the development of Newark. In a letter written by Israel Dille, a former mayor of Newark and antiquarian, he refers to one of the mounds at the site that was destroyed during the excavation of one of the Ohio Canal locks, in 1827. He proclaimed that when the mound was removed, 14 human skeletons were found buried 3 feet below ground, along with a large quantity of mica sheets.


During the early 1800s, the burial mounds belonging to the Cherry Valley Ellipse were looted. Precious ceremonial ornaments, including copper and mica items, were removed, never to be recovered.


The sole surviving artifact associated with the Cherry Valley Ellipse is commonly known as the Newark Shaman. This artifact, approximately the size of a softball, depicts a figure adorned in a bearskin, cradling a human head in its lap. It is believed to symbolize a shaman in the act of pulling down the bearskin over his own face, a ritual preparation possibly related to the burial or burning of a decapitated Hopewell head. Currently, the artifact is safeguarded and exhibited at the Ohio History Center in nearby Columbus, Ohio.


Visiting the former site of the Cherry Valley Ellipse is permitted, however there are no visible earthworks. Apart from a commemorative placard near the intersection of Union St and Wehrle Ave, there are no signs that anything once occupied the area.


Hopewell Earthworks Design Patterns

The architects behind Newark's monumental structures demonstrated extraordinary precision in creating expansive geometric designs. On numerous occasions these unique configurations adhered to consistent dimensions. For example, the diameter of the circular embankment within the Octagon Earthworks site, when squared, fits perfectly within the octagon enclosure itself. In addition, the distance between the Great Circle and Octagon enclosure is equal to exactly six of these squares if they were lined up side-by-side. An even more remarkable example is that the original square perimeter of Wright Earthworks is precisely equal to the circumference of the Great Circle. This is known as "squaring the circle," a sophisticated mathematical process that no other prehistoric civilization prior to or since, accomplished. Finally, the circular embankment found at the Octagon Earthworks shares an identical diameter of 1,054 feet with two other Hopewell circular enclosures, specifically those at High Bank Works and Hopeton Earthworks, both located more than 60 miles to the south in Hopewell Culture National Historical Park. These findings demonstrate that Hopewell architects employed a standardized square with a side measuring 1,054 feet as the basis for their units of length when designing earthworks. As a result, they constructed expansive circles, squares, octagons, and ovals, each with nearly equivalent areas.

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