Ruin in Craigmillar

I returned to Craigmillar as the trails are nice to run on and I could check in Cameron Toll for some yeast.

There is a ruin in one of the patches of woods. It is on the orienteering map. I have no idea what date the building is from or what its use was. The surrounding terrain is very craggy, steep and bumpy (good for orienteering) which is why I wonder why there was a building there in the first place. Potentially mining but who knows.

Still no yeast but I've just made enough chilly for a week so I'm less bothered.