Book excerpt: The premier monument is Durham Cathedral, greatest of English Norman churches. Lovers of the Middle Ages will also seek out the county's exceptional Anglo-Saxon churches, while many of its great castles - Brancepeth, Raby, Auckland, Lambton - conceal palatial Georgian and Victorian interiors. The landscape varies dramatically, from the wilds of Teesdale and Weardale, in the west, to the pioneering industrial ports of Sunderland and Hartlepool on the coast, including fine gentry houses and stone-built market towns. South Tyneside and northern Cleveland, historically part of County Durham, are also covered.