Well, yesterday morning I finally got around to going back to my father's land and digging up those mounds. And what did I find?

Nothing.

Yeah, I know. It was very anticlimactic, and I'm as disappointed as you guys that were following this story probably are. I dug up two different mounds to about three feet deep, and there was nothing there but more dirt and rocks. I was really hoping for a body or maybe buried treasure, but no such luck. I still think the mounds may be man-made, but I guess they'll have to remain a mystery.