As you cross the Trent, you are very much aware that you have moved from the south to the north country. The next great divide is the Tyne, with the dramatic straggle of Newcastle stretching east and west. Beyond lies mile upon mile of Northumberland, all the way to the Scottish border, arable land for grazing (punctuated with coal mines) by the coast, giving way to heathery moors and countless sheep. The centre of this often wild and always beautiful land is Alnwick, with roads stretching out, to north and south the Great North Road, east to the fishing port of Alnmouth, westward to the Roman Wall and the Cheviots. Alnwick Castle was the centre of the defence against invaders from the north, seat of the Percy family, Earls and Dukes of Northumberland.