The remains of the oldest European fort in the inland United States - dating back to 1567 - have been discovered in the Appalachian Mountains by archaeologists.
The findings provide new insight into the start of the US colonial era and the all-too-human reasons spoiling Spanish dreams of gold and glory, researchers said.
Spanish Captain Juan Pardo and his men built Fort San Juan in the foothills of the Appalachian Mountains in 1567, nearly 20 years before Sir Walter Raleigh's "lost colony" at Roanoke and 40 years before the Jamestown settlement established England's presence in the region, they said.
"Fort San Juan and six others that together stretched from coastal South Carolina into eastern Tennessee were occupied for less than 18 months before the Native Americans destroyed them, killing all but one of the Spanish soldiers who manned the garrisons," said University of Michigan archaeologist Robin Beck.
Beck is working with archaeologists Christopher Rodning of Tulane University and David Moore of Warren Wilson College to excavate the site near the city of Morganton in western North Carolina, nearly 482 km from the Atlantic Coast.
The Berry site is located along a tributary of the Catawba River and was the location of the Native American town of Joara, part of the mound-building Mississippian culture that flourished in the southeastern US between 800 and about 1500 AD.
In 2004, Beck and his colleagues began excavating several of the houses occupied by Spanish soldiers at Joara, where Pardo built Fort San Juan.
Pardo named this small colony of Spanish houses Cuenca, after his own hometown in Spain. Yet the remains of the fort itself eluded discovery until last month.
"We have known for more than a decade where the Spanish soldiers were living," Rodning said.
"This summer we were trying to learn more about the Mississippian mound at Berry, one that was built by the people of Joara, and instead we discovered part of the fort. For all of us, it was an incredible moment."
Using a combination of large-scale excavations and geophysical techniques like magnetometry, which provides x-ray-like images of what lies below the surface, the archaeologists have now been able to identify sections of the fort's defensive moat or ditch, a likely corner bastion and a gravelled surface that formed an entryway to the garrison.
Excavations in the moat conducted in late June reveal it to have been a large V-shaped feature measuring 5.5 feet deep and 15 feet across.
Spanish artifacts recovered this summer include iron nails and tacks, Spanish majolica pottery, and an iron clothing hook of the sort used for fastening doublets and attaching sword scabbards to belts.
Fort San Juan was the first and largest of the garrisons that Pardo founded as part of an ambitious effort to colonise the American South.