Updated

No wonder historians haven't been able to find a historic but long-lost French fort in America: They were looking in the wrong state. Researchers from Florida State University say Fort Caroline—which one calls "the oldest fortified settlement in the present United States"—isn't near Jacksonville as long thought, reports Heritage Daily.

The 1564 fort was actually on Rhetts Island near the mouth of the Altamaha River. That's about 70 miles away. In Georgia. The discovery would upend some long-held notions about the colonization of the New World and likely disappoint the Fort Caroline National Memorial—in Jacksonville.

But there's a big caveat: "We don’t have archaeological proof of the fort at this time,” says FSU's Fletcher Crowe. Instead, the announcement at a conference is based in part on a detailed analysis of old French maps and coastal charts of the US. “We haven’t found [the fort], but we are pretty much closing in on the site," adds co-researcher Anita Spring." The pair also say they've amassed loads of circumstantial evidence. For instance, they say Native Americans near the fort spoke a language known as Guale, and those speakers lived around what is now Darien, Ga., near the newly proposed site. It's definitely "provocative," a University of North Florida archeologist in the Jacksonville camp tells the Florida Times-Union. But “I don’t think it’s enough of an argument for me to change my mind.” It's not clear when actual digging might start to resolve things. (Click to read about how historians are closer to learning why colonists on North Carolina's Roanoke Island disappeared.)

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