Herdsmen herd livestock during the nomadic migration on the Ar Horqin grassland in Chifeng City, north China's Inner Mongolia Autonomous Region, May 31, 2019. Yearly nomadic grazing is still a tradition for people live on the Ar Horqin grassland, where was listed of National Important Agricultural Heritage Systems in 2014. For a long time, herdsmen would decide the route and time of yearly nomadic grazing according to the growth of grassland. (Xinhua/Peng Yuan)