Out at a place built by the Civilian Conservation Corps back in 1935/36. Found this while walking around. I think this was used for surveying changes to the land around where I am, as this area was dammed in the 1930s.
I've been searching for something specific to these but I think due to their age it might be lost to time.
Iirc, the YouTube channel half as interesting have a video about them
I'm going to go look for that. Thanks for the tip. I see this particular one every time I come to this place to go camping and I've never bothered to look anything up about them, though I've seen this one a thousand times possibly.