CHENGDU, Aug. 8, 2016 (Xinhua) -- Tourists walk on the iron-chain Luding Bridge across the Daduhe River in Luding County, southwest China's Sichuan Province, Aug. 7, 2016. Luding Bridge, constructed in 1705 in the Qing Dynasty (1644-1911), was an important place in the Long March of the Red Army. (Xinhua/Jiang Hongjing)