About 200 feet off the Chicago shoreline, covering about a quarter of an acre, is an underwater pocket scientists find fascinating.
And the mysteries of Lake Michigan are always inviting them to learn more.
It's called Morgan Shoal and it is a shallow body of water, with a rock hard bottom and a whole bunch of stories to tell.
What lies beneath is a rocky outcrop that has scientists like Phil Willink studying it closely now for a year and a half.
Willink is a senior research biologist from the Shedd Aquarium in Chicago.
"Morgan Shoal is the compressed remains of a coral reef that formed over 425 million years ago,” Willink says. “Way back then Chicago was actually south of the equator in a shallow tropical sea covered by coral reefs. Over time those coral reefs compressed into a super hard rock and it is still there today."
But there's more to the study that intrigues Willink and his crew.
It’s the site of a ship wreck.
The Silver Spray went down on July 15, 1914. It was on its way to pick up U of C students and take them to Gary, Indiana to look at steel mills. But it ran aground near 48th Street – on Morgan Shoal.
"Eventually the boiler fell out onto the bottom, the propeller and drive shaft -the rest of the boat was made of wood and drifted away," Willink says.
No one died but the boiler is still there over 100 years later.
It is a great historical landmark that has also created an outdoor classroom for experts on all things aquatic.
"We've used sonar to map the bottom, nets and traps to see what fish are out there, looked at rocks to see what aquatic insects are living out there, drones and remotely operated vehicles, divers,” Willink says. “We've used all these different types of methods and each tells us a slightly different story."
They have also used virtual reality camera to capture a 360 degree perspective. The hope is to share it with the public so more people care about the lake.
"One of the biggest dangers we face with the Great Lakes and Lake Michigan in general is we take it for granted."
Experts at the Shedd say fish are drawn to the Silver Spray wreckage, but they don't know why.
"One day's worth of effort at Morgan Shoal is equivalent to all the biologists over one year in the entire state of Illinois,” Willink says.