Fernie Castle - the fairly old bits
It is an interesting game to try to pick out the older parts of such buildings as this! Starting from the right, and ignoring the ugly little yellow harled extension lurking in the shadows behind, we start off with a large round tower, which one can be quite confident is not 'original', because the Scots didn't build conical roofs as tall and narrow as that until the 18th or 19th century. The only problem with that bold pronouncement is that a shot-hole can be clearly seen to the left of the lowermost window, however I suspect this was to give the work Scottish Baronial authenticity, and was moved there from some other part of the building during extension work!
(I wonder how they repair slates on the tower roof!?)
The next part of the building, the three storey section with the crow-stepped gable and the Virginia Creeper growing on it, is also not part of the original castle, although it may well have been built in the late 17th century. It is the next two sections of the building, the tallest parts, that are the oldest, although the effect is rather spoilt by the ugly 'castellated' thing that has been built onto the front.