Housed in a former munitions depot in a fortress on the outskirts of Berlin is an exhibition like no other: a veritable car boot sale of statues – damaged, dismantled or dumped – dating from medieval times to the Nazis to Communism. Unveiled: Berlin and Its Monuments has for the past eight years cast an unvarnished light on German history. Yet almost no Berliners have heard of it. I am standing in the courtyard of the citadel at Spandau, a place that has had many purposes since its first recorded mention in 1197, few of them reassuring. From the late...