I used to own this lovely stone barn, it came as just one of the impressive buildings that accompanied a rather grand farmhouse I bought when I first moved to France in 1972; aged 25.
It had not been touched since it was built in 1860-ish. Everything was original, and all the old carved wooden cow stalls were still there in perfect condition. The interior roof timbers were magnificent.
We now live about 300 metres away, so I pass by almost daily on my walks with the dog.
Amazingly, during all those years that I owned the barn (and since) I'd never noticed this L shaped stone built into the back wall. It must be the corner of an old broken water trough, or a sink maybe. I think one of the original builders must have been feeling 'frugal'.
Since I've noticed it, it now sticks out like a sore thumb, and I can no longer pass by without admiring it and smiling.
Incidentally, life is so much more pleasant in our present, much smaller, bijou cottage, but I do wish I could have brought this wonderful old barn with me; it's about 4 times the size of the cottage.