So, the owners before us liked to garden. Loved would be more accurate. They loved to garden. We were astonished when spring game, because things started growing everywhere. We basically dug everything out, because it was growing over itself and we weren't gardeners. In trying to clean up the yard, we came across a multitude of these rocks.
I had the foolish idea to dig them out. It was a horrible endless task that I worked on for a week before giving up. I gave up so much that these rocks stayed on the driveway for a few weeks after that, and I drove over them in disgust. Eventually I shoveled them into a container and later dumped them on the side of the house, where there were already tons. These pictured were just from one of the three planting beds filled with rocks.