When a scuba diving instructor stumbled across a carved tree trunk at the bottom of Lake Mendota in May 2022, maritime archaeologists quickly confirmed that it was a dugout canoe carved from a single piece of oak. The same instructor had found something similar the year before, but radiocarbon dating indicated that this craft was built around 1000 BC, making it the oldest ever canoe found in the Great Lakes region by more than 1,000 years.

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