Aerial photo taken on Aug. 19, 2020 shows people visiting flower fields at Nanniwan scenic area in Yan'an, northwest China's Shaanxi Province. (Photo by Qi Xiaojun/Xinhua)

Photo taken on Aug. 25, 2020 shows flower fields at Nanniwan scenic area in Yan'an, northwest China's Shaanxi Province. (Photo by Qi Xiaojun/Xinhua)