Every December, on the shortest day of the year as fall officially gives way to winter, a feat of ancient astronomy and mathematics is on display in the Southwestern Ohio community of Oregonia. The sun rises perfectly aligned in a gap along the earthen wall surrounding Fort Ancient Earthworks & Nature Preserve.
"Winter solstice is a special time out at Fort Ancient — along with a few other dates throughout the year — because this is one of the time periods that people 2,000 years ago were observing," explains Bill Kennedy, site manager. "We know that because of the astronomical alignments built into the earthwork at Fort Ancient, that the sunrise on the winter solstice is a time that they were observing."
Kennedy estimates around 200 people turned out early Thursday, Dec. 21. to mark the occasion.
"This is the best turnout we've actually ever had for a winter solstice here at Fort Ancient," he said. "Typically we wouldn't see more than about 80."
Tara Sikora came down from Columbus with her husband and three children to witness the sunrise alignment. She says they moved to Ohio recently and she's always wanted to see this. She hopes her children enjoyed it, too.
"I just hope they get the sense of community; that we really are a part of this whole human race that all experiences these amazing things."
RELATED: Ohio's Hopewell Ceremonial Earthworks are now UNESCO World Heritage Sites
Russel Rice lives just across the Little Miami River from Fort Ancient and frequently walks the trails around the area. He's witnessed more than a few alignments. He says he gazes at the mounds with wonder.
"Just the fact that the ancients were able to build these mounds with baskets (of dirt) carrying up from the river and getting the alignments right (such) that 2,000 years later it's still working."
It remains unknown why the solstice was important to these early American Indians, but it's clear that certain observable astronomical alignments were valued since they are built into so many of Ohio's mounds.
Fort Ancient is one of eight sites collectively known as Ohio's Hopewell Ceremonial Earthworks. They were inscribed earlier this year on the prestigious list of UNESCO World Heritage Sites, elevating them among locations considered of outstanding universal value such as the Pyramids, the Great Wall of China, the Historic Sanctuary of Machu Picchu, the Great Barrier Reef, and the Grand Canyon.
"We know that the American Indians that built Fort Ancient and these other Hopewell sites, they were very skilled observers of the sun. We also know that, even more so, they were observers of the moon and they also observed the lunar cycle. We don't know the exact nature of what kinds of things they would do to celebrate or observe these important moments but it was clearly something that they did for many generations," says Kennedy.
This year's winter solstice on Dec. 21 is the first astronomical alignment since Fort Ancient and the other earthworks were added to the World Heritage list. Tourism officials are expecting visitor numbers to increase across all the sites — as they have for other World Heritage locations — in the coming years as people around the world travel to see these important sites.
"Typically for the winter solstice, we'll usually see about 80 to 100 people and they're generally people coming from the local community, though it has already been growing in recent years [with people coming from further away]," Kennedy says. "We think with World Heritage, that this is something that's going to continue to grow... we do expect it to grow significantly over the coming years."
The gates open for this year's observance on Dec. 21 at 7:00 a.m. There will be a brief presentation around 7:30 a.m. and sunrise will occur at approximately 7:53 a.m.
"First and foremost these are American Indian sites, and they are sacred to American Indians and it's important to always show respect."
Kennedy notes that means, for example, not walking or climbing on the earthworks. Ohio History Connection, which operates the site, and the National Park Service work with 46 tribal partners with ties to Ohio to make sure they're abiding by their wishes and observing "a certain air of dignity around these sites."
"Especially on special days like this, what most people are coming out to experience is contemplation, and reflection, and that's the environment that we want to provide. These are incredible monuments. But they are places that are sacred to to some people and it's important to respect the American Indian wishes about how these sites are to be cared for."