Archaeologists have discovered stone tools atop a hill in this northern Minnesota town that may be 13,000 to 14,000 years old, according to a report published Thursday.
From the rough stone tools, archaeologists are speculating that "we're looking at certainly the relatively earliest occupants of the North American continent," biologist and archaeologist Matt Mattson told the Minneapolis Star Tribune. He worked on the project for the Leech Lake Heritage Sites Program, which is based near Cass Lake.
Britta Bloomberg, Minnesota's deputy historic preservation officer, said it may be among the oldest known archaeological sites in North and South America. A half-dozen archaeologists, soil scientists and others who have examined the site all said the artifacts are genuine, she said.
The stone tools were found while archaeologists were investigating the path of a road where the city is planning to expand for a community center, housing and businesses.
Archaeologists found 50 or more objects while digging through an area of about 50 square yards. The artifacts ranged from large hammer stones to small hand-held scrapers.
Mattson said the objects were found underneath a band of rock and gravel that appeared to have been deposited by melting glaciers and then covered by windblown sediment, Mather said.
David Mather, state archaeologist for the National Register of Historic Places, said the find "is something off our radar. We didn't think it was even possible in Minnesota."
"(This) could be a real watershed for understanding Minnesota's history," he said.
Mather said the site appears to be "much older" than the Clovis era of finely made spear points that defines the paleo-Indian period.
The find is "startling enough that appropriate response from every archaeologist and glacial geologist is skepticism." But, he added, a half-dozen archaeologists, soil scientists and others who have examined the site all say the artifacts are genuine.
Human remains, wood or textiles, if there were any, would have dissolved long ago in the acidic soil. The oldest human remains found in Minnesota belonged to the Browns Valley Man, who lived about 9,000 years ago. His remains were discovered in 1933 in a gravel pit near the town of Browns Valley in western Minnesota.
Walker is about 190 miles (300 kilometers) northwest of the Twin Cities.