MINNEAPOLIS (WCCO) -- Beginning this week -- and every Saturday throughout the summer -- park rangers will be hosting guided tours.

You choose which route: Harriet Island, Stone Arch Bridge or Fort Snelling.

We asked the rangers to give us a little sneak peak.

If you're looking for a kid-friendly weekend adventure, look no further than the Mississippi.

"The human race has had a lot of impact on the Mississippi River, including dams, and cities along the river," Ranger Abby Olson said. "We talk about how it's become a human river along this area."

In addition to learning the history of the river and Minnesota's natural parks, you might just find a treasure along the way.

Like this shale rock that carries evidence of our state's history.

"We've got old plants here, shells here -- animals from almost 450 million years ago," Olson said.

Up to 20 bikers can go on tours that run from nine to 14 miles -- it's "exercise enlightenment."

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