http://intellivex.com/case_studies.html A week ago, Mark Mihal disappeared into the fairway of the fourteenth hole at Annbriar Golf Course, in Waterloo, Illinois, a suburb of St. Louis. “I felt the ground start to collapse and it happened so fast that I couldn’t do anything,” he said later (as reported by his wife). “I reached for the ground as I was going down and it gave way, too. It seemed like I was falling for a long time. The real scary part was I didn’t know when I would hit bottom and what I would land on.” You can read a longer account on Mihal’s fantasy-golf website.
As it happens, I have a long article about sinkholes in the current New Yorker. (You won’t be able to read it online unless you’re a subscriber, I’m afraid.) The sign in the photo below, from a state park in Florida—which has even more sinkholes than Illinois does—explains what they are:
Most of the lakes in Florida were formed by the same processes that form sinkholes, and if you do a quick flyover of the state on Google Earth you will see lots of bodies of water that look similar to the one in the photo below, which is in another state park. It’s called Big Dismal Sink, and an old swinging rope overhangs it. If you decide to jump in, you won’t need to worry about hitting bottom, since it’s more than eighty feet deep.
I also visited Lake Jackson, just north of Tallahassee. It’s a four-thousand-acre natural body of water that occasionally disappears down a sinkhole, like a bathtub emptying down a drain. When it goes, it takes everything with it—fish, turtles, alligators, range balls, everything. You can read more about that in my article, and you can actually watch it happening here: