Free State High School junior Adam Ziegler was recently involved with an archaeological survey that helped in confirming the existence of an ancient Native American city near Arkansas City. Ziegler is pictured on Tuesday outside his Lawrence home.

Over the river and through the wood, to Grandmother’s house — and the site of a long-lost Native American city — Adam Ziegler went. What the Lawrence teen found while visiting his grandma near Arkansas City would prove what academics had suspected for years but never confirmed: the location of Etzanoa, a pre-Columbian civilization at the confluence of the Walnut and Arkansas rivers.

The city, once home to an estimated 20,000 Wichita Indians, could be the second-largest Native American settlement found in the United States, according to Donald Blakeslee, the Wichita State University anthropologist who led efforts in surveying the area. Radiocarbon dating suggests the Etzanoa lasted from about 1425 to the early 1700s.

And it was Adam, then a freshman at Free State High School, who stumbled upon the evidence that Blakeslee and his team used to pinpoint the location of Etzanoa. His discovery — a small iron ball buried about 4 inches into the ground — confirmed to Blakeslee and his team the location of a 1601 battle between Spanish explorers and Indian warriors at the Etzanoa site.

“They’d just found all kinds of trash and cans and bottle caps and stuff,” Adam, now a junior at Free State, recalls of his weekend trip to Grandma’s.

“So they quit looking after a few hours, but (Blakeslee) could just tell that I was so interested that he was just being nice and said I could go play with his metal detector and look around,” says Adam, who spent the next few hours surveying the area before discovering the canon ball.

Adam suspected that his find might be significant, he says, because he knew anthropologists were looking for lead possibly fired from muskets. When an excited Blakeslee had the iron ball analyzed, confirming that it had come from a Spanish canon, Adam knew he’d played a crucial role in discovering the lost city of Etzanoa.

Adam Ziegler, pictured here in this 2015 photo, holds the iron ball that he found while surveying an area near Arkansas City. Ziegler's discovery confirmed to anthropologists the location of the long-lost Native American city of Etzanoa.

Two years later, the story has gained national and international media attention, he says, after the Kansas House of Representatives formally recognized efforts to uncover the history of the long-gone settlement. The resolution, approved on the House floor April 5, has probably been Adam’s “biggest” watershed moment since this all began, he says. The interviews with multiple media outlets, including one earlier this month for NPR’s “All Things Considered,” have also been pretty memorable, he says.

It’s been one proud moment after the next for Debby Ziegler, Adam’s mother. Seeing her son recognized by the state Legislature was a particularly “poignant” experience, she says. But the older Ziegler also says she wasn’t exactly floored by the news, either.

“When people hear this story, they say, ‘Well, of course it would be Adam,’ because it’s just so fitting to his personality,” says the elder Ziegler, who teaches math at Free State High School.

“He’s been this way his whole life, since he was little,” she says of her son, one of four Ziegler kids. “He’s always got some project, or building a pond or an invention or exploring something.”

Just last Sunday, she says, Adam brought home a fully inhabited bee hive, which now sits, bees a-buzzing, in the family’s backyard. It’s his latest in a string of projects, Adam says.

Right now, he’s also considering starting up his own business, though Adam remains tight-lipped on what exactly that business might entail. He doesn’t want people stealing his idea, he says. Like his maternal grandfather, retired Lawrence biology teacher and conservationist Stan Roth, Adam’s interested in wildlife, too. Recently, through the University of Kansas, he’s been involved with the Topeka Shiner Project, a conservation effort to recover the federally endangered Topeka shiner fish species.

Since Adam’s fateful discovery at the Etzanoa site, Arkansas City officials have discussed potential development around the location of the old settlement. Anthropologists have said Etzanoa may be comparable in size to Cahokia, the largest Native American urban settlement built in the United States. The Cahokia Mounds State Historic Site in Illinois attracts about 400,000 visitors a year to its packed-earth, 14.4-acre pyramid that was once the ancient city’s central jewel.

Etzanoa doesn’t have any pyramids, but Arkansas City officials hope the discovery will bring a boost to the small southern Kansas community.

All because Adam “just happened to be at the right place, at the right time,” he says. His mom says her son could have easily passed on Grandma’s invitation to visit that weekend while anthropologists surveyed the area. But Adam also says he was “lucky enough to get the opportunity,” and curious enough to follow up on it.

Now, he’s a teenager who’s rewritten history.

“Always be up for adventures,” the 17-year-old says. “Take opportunities when they come.”