Aerial photo taken on Dec. 17, 2016 shows a bullet train running in a trial operation on the Yaoguantun Bridge of the 2,266-kilometer Shanghai-Kunming high-speed railway in southwest China's Guizhou Province. The railway linking Shanghai in east China and Kunming, capital of southwest China's Yunnan Province, is planned to be put into operation at the end of this month. (Xinhua/Ou Dongqu)