Berriedale Castle (2)
Although the seaward side of the site is not as naturally protected as the west side, the castle site was surrounded by a massive encient wall, the foundations of which are still visible in places.  Direct access to the castle was controlled by a foss or ditch, which although doubtless enlarged, by quarrying, appears to me to be a natural fault line.  

As seems to be the usual case in these Caithness coastal castles, there were buildings on both side of the narrow courtyard.  The oblong structure to the landward (left) side, was the keep, and there were stables on the other side.  At this end, a massive wall prevented any intrusion down the sides of the outer wall, and a gatehouse and drawbridge controlled the approach. 
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