PEEBLES, Ohio -- The earthwork likeness of a serpent draws more than 23,000 visitors each year to north Adams County.
It measures 1,348 feet in length and is 30 feet wide; it is one of 58 Ohio Historical Society historic sites and museums, and became a National Historic Landmark on July 19, 1964, as designated by the U.S. Department of the Interior.
It was recently named as one of four "Sacred Places of the World," by a subsidiary publication of National Geographic.
It's even advertised on U-Haul trucks as one of America's places of adventure.
Serpent Mound State Memorial in Adams County is the largest prehistoric earthen serpent mound in the world, but its origins are still a mystery to those who have studied it over the years.
"It attracts people from all over the world," said George Kane, director of historic sites and facilities for Ohio Historical Society.
Managed by the Arc of Appalachia on behalf of the Ohio Historical Society, Serpent Mound will once again be the setting of an archaeology investigation beginning April 8, with the purpose of determining the age of the mound, which can also help identify what culture built the mound.
"It's still an open question as to who built the mound," said Brad Lepper, senior curator of archaeology with the Ohio Historical Society. Lepper is no stranger to the age of the mound, having written a paper on the serpent mound in 1998.
The question is who built the mound, and when, Lepper said.
Was it built by the Adena culture that lived in Ohio from 800 B.C. to 100 A.D. or those of the Fort Ancient culture, who lived in the area from 1000 A.D. to 1650 A.D?
To make that determination, Dr. William F. Romain, Ph.D, a research associate with the Ohio State University Newark Earthworks Center, has been given approval by OHS to conduct the archaeological investigation.
The investigation will do remote radar sensing of the earthwork and will extract small-diameter soil cores from various point in and around the mound to obtain samples of charcoal from an "ash layer" that Frederic Putnam of Harvard University's Peabody Museum identified when he excavate portions of the mound in the 1880s.
According to Sharon Dean, Ph.D., OHS director of museum and library services, the age of the samples could be determined with radiocarbon dating and provide additional evidence to help scientists determine when the earthwork was built.
Lepper explained the mound is built completely of earth, with some stones used to keep the sides from eroding. Depending on the size of the village, with a large enough group of people, the mound could have been completed over a summer, Lepper said.
There are no trees on the mound, which is covered in grass. There are walking trails around the Brush Creek Valley that lead from the mound, rock shelters in the hillsides and an abundant variety of plants and wildflowers, such as red trillium which was used by Native Americans as an aid in childbirth or as a poultice for tumors and inflammation.
Others have studied the mound, dating as far back as 1846, when Ephraim Squier and Edwin Davis of Chillicothe made observations of it. According to Brad Lepper's 1998 paper, "they wrote that in 1846 the serpent was "upwards of five feet in height by thirty feet (in width at the) base." They mapped its "graceful undulations," flowing along the curve of a precipitous spur of land, from its coiled tail to what they described as gaping jaws "in the act of swallowing or ejecting an oval figure." The oval embankment was 4 feet in height and 160 feet in longest diameter. In the center of this enclosure, was a small mound of "large stones much burned." Squier and Davis concluded that the shape represented a serpent with an egg in its mouth. Reasoning that similar symbols figured prominently in the religious art of "Egypt, Greece, and Assyria," as well as the "superstitions of the Celts, the Hindoos, and the Chinese," Squier and Davis speculated that the similarity bespoke an "affinity with the far-flung cultures."
In 1848, Serpent Mound was described in the Smithsonian Institute's publication, "Contributions to Knowledge Series No. 1."
At one point after Squier and Davis' study, a tornado uprooted trees surrounding the mound that provided protection and a landowner began to plow over it.
In 1886, Frederick Ward Putnam of Harvard University's Peabody Museum began work to study and preserve Serpent Mound. Funds were raised to buy the property and from 1887-1889, Putnam conducted excavations into the mound as well as nearby burial mounds and prehistoric village.
Lepper explained during an interview Thursday there are three burial grounds and one village on the site which have yielded evidence of two Native American cultures: Adena and Fort Ancient. Lepper said two of the burial grounds are Adena, the third Fort Ancient.
At the conclusion of his exploration, Putnam restored the mounds and the Peabody Museum, as the property owner, made it the first prehistoric site in North America to be preserved as a public archaeological park. The Peabody Museum operated the park until 1900, when it deeded the property to the Ohio Archaeological and Historical Society, now the Ohio Historical Society.
During the Great Depression, federal public works projects were responsible for the building of the picnic shelter, public restrooms and the museum, which provided a gathering place for family outings, said Kane. Today, those same amenities are available to visitors to the park, which is open year-round, weather permitting, except for the museum, which closes during the winter season.
"This site gets a lot of statewide, national and international attention," said Kane, who also credited the organization Friends of Serpent Mound with the annual events surrounding the Serpent's astronomical alignments with the winter and summer solstice sunrises, and the equinox sunrise.
Serpent Mound is located on Ohio 73, six miles north of Ohio 32 and 20 miles south of Bainbridge in Adams County. For more information, visit www.ohiohistory.org/serpentmound.
References used were Great Serpent by Bradley T. Lepper and Archaeology in America -- An Encyclopedia, Volume 2.