(VOVworld)- Lang Son province has launched an exhibition featuring the Then culture heritage. On display are 300 objects and photos of the Vietnam Museum of Ethnology and museums in the northern region. This is part of a series of events to highlight Then singing at a national festival. The exhibition highlights musical instruments and costumes used in Then singing and local ritual ceremonies. They confirm the time-honored tradition of Then singing as a preparation for the dossier to be submitted to the UNESCO for its recognition of Then singing as an intangible cultural heritage.