Built almost 2,000 years ago by the Roman occupiers of Britain, Hadrian's Wall is one of the most famous and identifiable World Heritage Sites. When two old friends, one American and one British, reunited to trek the length of the Wall, they reminisced about the past while sharing apprehension about the future. This memoir of their coast-to-coast voyage examines Roman history, drawing parallels between the fall of the Roman Empire and the recent...