The history of the border between Scotland and England is rich in battles, treaties, castles and crossroads. But the border also provides a means of looking more closely at the changing natures of the two countries it joins and separates. Alistair Moffat is a life-long borderer and the ideal guide on a one-hundred-mile journey from Berwick-upon-Tweed to the mouth of the river Sark. This is a history book, a travelogue, a personal reminiscence, a gently prodding examination of national identity - and a celebration of a place and the people who live there.