The Hjemmefrontmuseum (Resistance Museum) occupies a distinctive old building just outside the castle entrance, an apt location given that the Gestapo had the habit of executing captured Resistance fighters a few metres away – after torturing them inside the castle first. Labelled in English and Norwegian, the displays detail the history of the war in Norway, from defeat and occupation through resistance to final victory. There are tales of extraordinary heroism here – notably the determined resistance of hundreds of the country’s teachers to Nazi instructions – plus a section dealing with Norway’s Jews, who numbered 1800 in 1939; the Germans captured 760, of whom 24 survived. There’s also the moving story of a certain Petter Moen, who was arrested by the Germans and imprisoned in the Akershus, where he kept a diary by using a nail to pick out letters on toilet paper; the diary survived, but he didn’t. Other acts of resistance included the sabotaging of German attempts to produce heavy water for an atomic bomb deep in southern Norway, at Rjukan, but there’s also an impressively honest account of Norwegian collaboration: fascism struck a chord with the country’s petit bourgeois, and hundreds of volunteers joined the Wehrmacht. The most notorious collaborator was Vidkun Quisling, who was executed by firing squad for his treachery in 1945. When the German army invaded in April 1940, Quisling assumed he would govern the country and made a radio announcement proclaiming his seizure of power, though in the event the Germans soon sidelined him, opting for military control instead.