In the wake of the EU referendum, the United Kingdom's border with Ireland has gained greater significance: it is set to become the frontier with the European Union. To uncover its secret landscape, with a troubled past and an uncertain future, Garrett Carr travelled Ireland's border on foot and by canoe. This invisible line has hosted smugglers and kings, runaways, peacemakers, protestors and terrorists, revealing the tumult of a border, changing the way we look at nationhood, land and power. From encounters with border dwellers to uncovering rituals, hidden pathways and ancient monuments, this book presents the borderland as a unique realm of its own, and asks what it holds for the future.