Aerial photo taken on May 16, 2018 shows builders working at the construction site of the Jingxi-Longbang expressway in the China-Vietnam border area in south China's Guangxi Zhuang Autonomous Region. The 28.3-km expressway, linking the Jiuzhou Village of Xinjing Township with the Longbang Port in Jingxi City bordering Vietnam, will open to traffic by the end of this year. (Xinhua/Lu Bo'an)