http://www.coztarica.com/2009/10/15/choosing-the-best-hiking-boot/

Surveying by the foot

This little marker is the gatekeeper to preserving the wilderness. It represents years of work and countless calculations to determine property lines and protect the Appalachian Trail. It is the evidence of a boundary survey that forever protects the Trail, exactly like a boundary survey protects your own property. But if you went out looking…