Re: "Trail marker?"
Notice there is some possible additional information in the lower and upper right circle To me it also looks like a soldier, feather. Its probably both that and...more concrete info.
Multiple meanings or signs built into one is what I see time and again. Another thing I wonder is if it is also an upside down bell shape though I do not see the knocker.
Of course the important pertinent information is the "triangle"/circle carvings. Though the bottom part of the triangle..is not really pointed so I would hesitate to call it a triangle. The things
I mention are just sidelights.
Also.. the face could be construed as a bears face too, with those little rounded ears on top at each side.