In this Jan. 13, 2016, photo, an archeology student at the University of West Florida uses water to sift through dirt for shards of pottery or other artifacts gathered from a research site near Pensacola Bay, Fla. Amateur archaeologist Tom Garner had time to kill after dining one day in Pensacola and took a drive along Pensacola Bay in the Florida Panhandle. Spying a newly cleared lot, he poked about in hopes of finding artifacts from the city's rich history dating to the earliest years of Spanish exploration. Surprisingly, Garner stumbled upon some broken shards of 16th century Spanish pottery. (AP Photo/Melissa R. Nelson)

Amateur archaeologist Tom Garner had time to kill and took a drive along Pensacola Bay in the Florida Panhandle. Spying a newly cleared lot, he poked about, hoping to find artifacts from the city's rich history dating back centuries to the Spanish explorers.

Garner stumbled upon some shards of 16th Spanish pottery.

"There it was, artifacts from the 16th century lying on the ground," said Garner, a history buff whose discovery has made him a celebrity in archaeological circles.

Experts have confirmed the find as the site of the long-lost land settlement of a doomed 1559 Spanish expedition to the Gulf Coast led by Tristan de Luna. The discovery bolsters Pensacola's claim as the first European settlement in the modern-day United States, six years before the Spanish reached St. Augustine on Florida's Atlantic seaboard. The expedition was scuttled by a hurricane in September 1559, shortly after the fleet arrived in Pensacola. Five ships sank.

Archaeologists diving in Pensacola Bay found part of Luna's doomed fleet in the '90s, including the anchor of one ship. But the exact site where Luna and 1,500 soldiers, Mexican Indians and Spanish settlers lived for about two years had eluded searchers—until now.

Many believed Luna's fleeting settlement had washed away in storms or was entombed beneath centuries of development.

Archaeologists from the University of West Florida are now digging in the quaint, waterfront neighborhood of homes and businesses.

John Worth, an associate professor of anthropology with the University of West Florida, specializes in Spanish colonial history and has studied Luna expeditionary documents. The university confirmed the find this fall and announced it to the archaeology world just before the beginning of the year.

"This gives us a whole new window on early Spanish colonialism here in the United States," he said.

Luna's mandate from the Spanish king was to construct a village that would include a church, government house, town plaza and residential site. The archaeologists hope to find out how far the work progressed.

Had Luna succeeded in colonizing the northern Gulf Coast, it would have changed the history of North America, Worth said.

A lasting Spanish foothold in the Panhandle could have checked later French influence on the region, he said.

Spaniard Pedro Menendez founded the first successful Spanish settlement at St. Augustine in 1565.

Cal Halbirt , city archaeologist for St. Augustine, said the discovery should add new understanding to Florida's colonial past.

"Having actual, tangible remains from the Tristan de Luna site is very important," he said. "I think, from a level of wow factor, it ranks right up there."

Meanwhile, St. Augustine proudly maintains its claim as the oldest continuously occupied European settlement city in the present-day U.S. "There is definitely community pride because of that," he said.

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