the construction of a tunnel on the kunming-vientiane railway was completed on sunday.
the jingkuan no. 2 tunnel, about 4.6 km long, is located in jinghong city of yunnan province.
the tunnel, with a super-large exit, has a 80-meter stretch with fault surface of 249 square meters.
the railway is a strategic docking project between the china-proposed belt and road initiative and laos's strategy to turn from a landlocked country to a land-linked hub.
the railway is scheduled to be completed and open to traffic in december 2021.