Hikaru Museum sits outside central Takayama in a building that deliberately borrows from ancient Mesoamerican forms. The collection is broad rather than narrow, with Japanese and international art, archaeological material, and cultural displays arranged under one roof.
It is most rewarding for travellers who have already seen Takayama's old merchant streets and want something stranger and quieter. Check transport before going, as the museum is not a casual wander from the historic centre.