Pictures #1 and #2. Someone REALLY fell behind on chinking between the logs there.
Pictures #3: Cimarron Canyon in New Mexico? (However, when I remember the one there, I remember it being more like waist level on an adult.) If so, when I was a youngster, our family used to camp there. I even remember catching a small trout with a can in that stream.
Those are old cabins off of a mining trail that we like to take.
The log was gone for a few years and then someone replaced it.