DUNSTAFFNAGE (Argyll) -- One of the old curtain-wall castles of Argyll, near Oban; this type of building (13th C) was a frequent pattern in western Scotland, consisting basically of a thick stone wall built around the edge of a large rocky extrusion, with a simple arched entrance passage (towers were added later) -- other examples are Mingary and Tioram, which I haven't visited. This style is stark and solemnly impressive. Dunstaffnage was the capital ('Dun') of the ancient Irish kingdom of Dalriada, Fergus and Ossian and that crowd. The famous Stone of Destiny was kept here until it was moved to Scone.
The castle is located near Oban in a flat built-up area along the shore of Loch Etive and is not very impressive until you come up close and see the rock it is built on. The keep/gatehouse, which is still roofed and floored, is a 17th C addition -- a tower house, in effect -- and the original defenses were rather weak apart from the scarp and high thick walls. But that was typical of early curtain-wall Scottish castles.