The Debatable Land was an independent territory which used to exist between Scotland and England. At the height of its notoriety, it was the bloodiest region in Great Britain, fought over by Henry VIII, Elizabeth I and James V. After the Union of the Crowns, most of its population was slaughtered or deported and it became the last part of the country to be brought under the control of the state. Today, its history has been forgotten or ignored. When Graham Robb moved to a lonely house on the very edge of England, he discovered that the river which almost surrounded his new home had once marked the Debatable Land’s southern boundary. Under the powerful spell of curiosity, Robb began a journey – on foot, by bicycle and into the past – that would uncover lost towns and roads, reveal the truth about this maligned patch of land and result in more than one discovery of major historical significance.