These scraggly rings of shells and prickly pear cactus hold what might be the most fascinating prehistoric structure on the coast. But Fig Island is a mystery.

And when it comes to curiosity seekers, its managers want to keep it that way.

The shell ring complex is among the largest known that are still somewhat intact. It’s comprised of one entire ring, the remains of at least two others with smaller ringlets and at least one causeway. The shell mounds rise as much as 13 feet high. They were built centuries ago by people who were among the first known to live here: hunter-gatherers.

“They’re not just trash piles,” said Sean Taylor, S.C. Department of Natural Resources Heritage Trust archaeologist. “This isn’t a ring; it’s a hexagon. Somebody designed it, brought people together to build it. It had some meaning. Unfortunately that’s part of the past we’re probably not going to get to.”

For the Lowcountry, it’s an incomparable deficiency. Fig Island, located in the Lowcountry estuaries, is maybe the most remarkable site on the Southeast coast.

This is a place that has been designated a National Historic Landmark, that at one point was proposed to be nominated as an esteemed World Heritage Site.

When Taylor and two other DNR staffers came ashore Fig Island recently to do a regular check of the site, they bushwhacked through the undergrowth of a hummock to reach the hexagon ring. As its circular shape became apparent, their steps slowed.

It was so quiet the echo of surf in the distance could be heard. The wind died off to a mood of abandon, a sense of haunt.

The place is a singular feature, something that would be a wonder to be viewed. For the general public, that’s not going to happen soon. There’s no money to secure the site, much less to do research or manage even supervised visitation. And it’s difficult to get to.

Because of that, the island is one of a number of publicly owned sites that are managed largely out of view, kept to the province of archaeologists, its location seldom disclosed.

At least a few of the people who show up unsupervised at sites like this one do it to maul them. Taylor brings up the Stallings Island archaeological site in the Savannah River, where rare bone pins were found. Vandals tore it up to loot them, to sell on the antiquities market, he said.

Before Taylor’s visit to Fig Island, crumpled beer cans had been littered around the carbon from a fire in the woods. A camp shovel, luckily not strong enough for the task, had been propped up against the post of a Do Not Disturb sign warning that Fig is an archeological site.

Nobody knows just how important a resource Fig Island might be. Native Americans began piling oyster shells there during the time of the earliest pyramids. In a relatively few years they presumably feasted on more than a billion oysters from the waters around the 20-acre hummock, shucking enough shells to fill a stadium full of Olympic-size swimming pools.

These were the Archaic people, until recently the first known people to inhabit South Carolina, turning up about 12,000 years ago and lasting as a cultural group until agriculture developed about 4,000 years ago. The rings are thought to have been occupied for more than 400 years.

The causeway, the smaller ringlets, the piling of more shells at some spots than others in the hexagon rings for what appear to have been enclosures — it all suggests a society.

“The big question: did they live here year-round, and where? In the rings. Or over there,” Taylor said, pointing to a nearby hummock island. “Were the rings habitated? Were they ceremonial?”

Norman Davis, an archeological contractor who helped survey the complex for the South Carolina Department of Archives and History in the early 2000s, thinks it might have been designed with the stars in mind.

“I have unpublished data that suggest Rings One and Two are aligned to the solstices and equinoxes and Ring Three may have been aligned to the rise and set of the constellation of the Northern Crown, about 3,500 years ago,” he said in an earlier interview with The Post and Courier. “The site was probably aligned to the sun and stars for ceremonial reasons.”

Fig Island could be made at least partly accessible to the public, using something along the lines of viewing platforms and an off-site education center for visitors. But keeping visitation non-intrusive is a headache waiting to happen at a fragile site that’s difficult even for its managers to get to. The island is not a park. It’s an archaeological trove.

“We’re really about access,” said Ken Rentiers, DNR deputy director of land, water and conservation. “How do you balance that and not have a site damaged or vandalized? You do your best to make sure nothing bad happens. We take our stewardship seriously.”

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