MARQUETTE (AP) -- Thousands of years of human activity along the Upper Peninsula's Lake Superior shoreline have come into sharper focus after three years of research.

Scientists from Northern Michigan University's geography department recently completed a project at Pictured Rocks National Lakeshore that located 23 new archaeological sites.

The researchers also helped define the shoreline as it existed 4,500 years ago.

Department head John Anderton says the National Park Service-backed effort was designed to find cultural resources so they can be protected during future road building and other developments.

He says the federally protected land isn't very habitable today but used to be a good place for hunter-gatherers to live.

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