…well, one of the largest, at any rate.

When I was flying into Midway airport this May, I was looking idly out the window, gazing down at the city spread below. There was a nice view of the Southside, and I swore I could see the University, and then…

Approx. view out of my plane window

???

I mentally filed away the gigantic hole in my memory, to be accessed later when I was on solid ground. Naturally, I promptly forgot all about it when the plane hit the tarmac.

But then a week later, my friend Michaela and I were debating the best way to escape from an awful Friday night party. After briefly considering intrusively following a homeless guy (we abandoned the effort after he politely declined), memories of the giant hole suddenly resurfaced.

A quick google search for “giant open pit mine chicago” revealed the existence of Thornton Quarry, apparently one of the “largest aggregate quarries in the world”. First started in 1924 by a guy named Colonel Hodgkins, it’s been under continuous operation for almost a century, digging out aggregate material for construction across Chicagoland. It used to be an ocean 300 million years ago, like the rest of Indiana, so there’s a bunch of random fossils there, and it’s going to be turned into a backup reservoir by the end of this year.

Also, it’s over 400 ft deep (>125m), meaning a 30 story tall skyscraper could comfortably fit in the bottom with its spire still not high enough to reach ground elevation. It’s also approximately 1.5 miles by 0.5 miles (2.5 km by 1 km), 1 mile (1.5 km) at its widest — which means you could not only fit the entire campus of the University of Chicago (approx 0.5 x 1 mile) into the depths of the quarry whole, you can almost fit the entire neighborhood of Hyde Park (approx 1.5 x 1 mile) in there.

Some hole.

A second google search revealed that this monstrosity was a mere 35 minutes south of the University of Chicago.

It was go time.

Image credit for the plane window pic: https://achicagosojourn.wordpress.com/