Plot: David Dimbleby travels north of the border to find out how Scotland developed a style of building quite different from that in England. Join him on a journey from the extraordinary visions of Stirling Castle to the Scottish baronial of Dunrobin; from the crofter's community of Gearrannan on the Isle of Lewis to Charles Rennie Mackintosh's masterpiece, The Glasgow School of Art; and ending up at the new Scottish Parliament building in Edinburgh