Norway's national museum of popular music, housed in a converted grain silo on the waterfront north of the centre. The exhibition runs decade by decade from the 1950s onwards, telling the story of Norwegian pop, rock, jazz, and electronic music through instruments, photographs, costumes, video, and interactive booths where you can try the gear yourself.
The building alone is worth the visit — a luminous cantilevered structure that has become a landmark on the harbour skyline. Allow two hours for the full exhibition. From the centre, walk twenty minutes north along the harbour or take any of the buses heading for Brattøra.