Named after the Norwegian Resistance group who occupied it between 1940 and 1945, this excellent reconstruction of a clandestine Resistance headquarters, uncovered by the Nazis in 1942, is now Bryggen's tiniest museum. It's an atmospheric experience, with vintage radios and wartime memorabilia.
Fittingly, finding it is still a challenge. It's behind the Enhjørningen restaurant; pass through the alley and up the stairs to the 3rd floor.