A girl in traditional Mongolian clothing sings a long tune at the Mongolian long tune Nadam, which concluded in Alshaa Left Banner in Alshaa League, in North China's Inner Mongolia autonomous region, on Aug 18. [Photo/IC]

A childrens' Mongolian long tune Nadam, was concluded in Alshaa Left Banner in Alshaa League, in North China's Inner Mongolia autonomous region, on Aug 18.

The Mongolian long tune -- otherwise known as the Urtin Duu -- is an historical Mongolian folk music song estimated to date back to the 7th century.

Experts say it was the time when the Mongolians were shifting from hunters along the Argun River, to a nomadic life on the western Mongolia grasslands. The Urtin Duu is now part of the Oral and Intangible Heritage of Humanity and the world's intangible cultural heritage.

During the two-day event, total of 37 kids in 10 teams from eight provinces and regions in China showcased their long tune singing skills in competitions and exchanged ideas and experiences with each other.