A visitor takes photos by the Luanniao Lake at Shandan horse ranch in Shandan County of Zhangye City, northwest China's Gansu Province, Sept. 10, 2019. In early autumn, Shandan horse ranch, located in the middle of Hexi Corridor in Gansu, shows a beautiful scenery. (Xinhua/Ma Ning)

　　A visitor takes photos by the Luanniao Lake at Shandan horse ranch in Shandan County of Zhangye City, northwest China's Gansu Province, Sept. 10, 2019. In early autumn, Shandan horse ranch, located in the middle of Hexi Corridor in Gansu, shows a beautiful scenery. (Xinhua/Ma Ning)

　　Aerial photo taken on Sept. 10, 2019 shows a herd of horses at Shandan horse ranch in Shandan County of Zhangye City, northwest China's Gansu Province. In early autumn, Shandan horse ranch, located in the middle of Hexi Corridor in Gansu, shows a beautiful scenery. (Xinhua/Ma Ning)

　　Aerial photo taken on Sept. 10, 2019 shows an early autumn scenery of the Luanniao Lake at the Shandan horse ranch in Shandan County of Zhangye City, northwest China's Gansu Province. In early autumn, Shandan horse ranch, located in the middle of Hexi Corridor in Gansu, shows a beautiful scenery. (Xinhua/Ma Ning)

　　Photo taken on Sept. 10, 2019 shows herdsmen and horses at Shandan horse ranch in Shandan County of Zhangye City, northwest China's Gansu Province. In early autumn, Shandan horse ranch, located in the middle of Hexi Corridor in Gansu, shows a beautiful scenery. (Photo by Du Zheyu/Xinhua)

　　Photo taken on Sept. 10, 2019 shows herdsmen and horses at Shandan horse ranch in Shandan County of Zhangye City, northwest China's Gansu Province. In early autumn, Shandan horse ranch, located in the middle of Hexi Corridor in Gansu, shows a beautiful scenery. (Photo by Du Zheyu/Xinhua)