Singers of the Kam Grand Choir from Kaili University in southwest China's Guizhou province perform on stage at the China National Arts and Crafts Museum, also known as the China Intangible Cultural Heritage Museum, in Chaoyang district of Beijing on Aug. 8, 2023. With a history spanning more than 2,500 years, the Kam Grand Choir, also known as the Grand Song of the Dong, is a type of polyphonic folk singing performed without musical instruments. The choir was included in UNESCO's Representative List of Intangible Cultural Heritage of Humanity in 2009. [Photo by Yan Bin/China.org.cn]