The classic zigzag split rail fence of early agricultural landscapes has a rich history and endures today. The abundance of wood in North America promoted the zigzag and was used to fence cattle (in and out) until another more efficient material-product entered the scene: metal-wire.
These wood fences were labor and material intensive and when the practical application for these fences were exhausted, most were abandoned for the landscape to reclaim. In the northeast, as fields were developed, plowed stones were removed from the fields and piled along the fence giving the original fence line more permanence in stone. The wood would eventually rot away, but the stone remained. Forests regenerated and where there were once fields. Without this explanation, the casual observer is puzzled by what they see. They cant imagine the very idea of building a rock wall meandering back and forth through trees.