What's the dark stuff in Lake Michigan off the coast of Chicago

The 'Christmas Tree Boat' Shipwreck That Devastated 1912 Chicago - Atlas Obscura

The battle for Lake Michigan: As beaches erode, millions of dollars have been poured into temporary solutions. Can anyone find a long-term fix? – Chicago Tribune

So Great, So Fragile: Great Lakes shorelines eroded, washed away after years of high water levels - ABC7 Chicago

Behold the Persistent Legend of our Deep Blue Waters: The Lake Michigan Sea Serpent

Chicago Accent 101 / Rebecca Gausnell - Voice & Accent Coach

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13 Most Scenic Drives in Chicago

An endangered piece of history beneath Lake Michigan's surface - Chicago Reader

DEEP DARK LAKE MICHIGAN, Ghost ships, pirates, tunnels & more: strange and sordid stories pulled from the depths of Chicago's inland sea. Guest speaker: Sam Prestigiacomo LINK

pizzapussy84 (u/codymason84) - Reddit

What is this in the middle of the Atlantic ? : r/geography

14 Things to Avoid in Chicago

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Red Summer In Chicago: 100 Years After The Race Riots : Code Switch : NPR