VIENTIANE - China Railway No 5 Engineering Group (CREC-5) told Xinhua on Wednesday that it has drilled through the Ban Konlouang Tunnel, a key bottleneck project of the China-Laos railway, 43 days ahead of schedule.

After the completion of the third longest tunnel of the railway, the CREC-5 has bored all its 10 tunnels, out of the total 75 of the railway in northern Laos, and has basically finished its offline engineering work.

The 9,020-meter Ban Konlouang Tunnel, in the Namor District of Oudomxay Province, some 400 km north of the Lao capital Vientiane, goes through harsh geological conditions of faults, underground rivers, high temperature, water inrush and mud, which makes its construction a key bottleneck project of the railway.

Since the start of the tunnel construction in March 2017, the CREC-5 has strengthened scientific study to develop multiple advanced engineering techniques and methods.

With the COVID-19 epidemic setting in, the Chinese engineering company also comprehensively implemented epidemic prevention and control measures during the construction.

The China-Laos Railway is a strategic docking project between the China-proposed Belt and Road Initiative and Laos' strategy to convert from a land-locked country to a land-linked hub.

The 414.332-km railway, with 198-km tunnels and 62-km bridges, will run from Boten border gate in northern Laos, bordering China, to Vientiane with an operating speed of 160 km per hour.

The electrified passenger and cargo railway is built with the full application of Chinese management and technical standards.

The project started in December 2016 and is scheduled to be completed and open to traffic in December 2021.