Workers work at the construction site of the arch bridge of Dali-Ruili railway over Nujiang River in southwest China's Yunnan Province, Dec. 30, 2019. The arch bridge of Dali-Ruili railway over Nujiang River, with a span of 1,024.2 meters, will shorten the travel time of Dali to Ruili from six hours to two hours after its completion. (Xinhua/Yang Zongyou)