Photo taken on May 21, 2017 shows a tunnel of China-Laos railway under construction in northern Laos' Luang Prabang Province. The China-Laos railway has a total length of 414.332 km with over 62.7 percent of bridges and tunnels, linking Mohan-Boten border gate in northern Laos and capital Vientiane. China-Laos railway is the first overseas route connecting with the railway system in China, using Chinese technology, equipment and investment. (Xinhua/Zhang Jianhua)
