Reminds me of this little park in Albany, GA. I can't recall the name of it, and don't care to look it up, but it's a nice green open park surrouned by roads and the only trees are around the edges, nice sized oaks. The odd thing you notice right away is how much lower than the surrounding land it sits. When I was a kid, I asked my mother about it and she told me that it was a lake when she was a kid and then it drained in a single night. Sinkhole opened up and it just sucked the water right down. After that the area was determined to be stable so they eventually made it into a little park.