One of the things I really enjoyed about hiking in the mountains were all the rock cairns along the trail. They are usually put there for a reason. If the trail gets confusing and you are not certain which way to go they are there as a directional sign for you to follow.
I found them both helpful and mysterious at the same time. I would always wonder who took the time to put them there. They are always built so carefully and well balanced.
Of course mine is not so well balanced but I take some artistic license here. Off balance is my thing after all.