Final tunnel on Indonesia rail line completed

The last tunnel on the high-speed rail line linking the Indonesian capital, Jakarta and the city of Bandung was completed on Tuesday, the thirteenth to be built along the line, marking an important milestone in construction, the China State Railway Group said.

The 142-kilometer line has 16,643 meters of tunnels, driven through complicated and sometimes unstable geological strata composed of clay, mud and sandstone. These relatively weak materials are subject to potential problems such as instability, deformation and even collapse, posing a challenge to construction.

The final tunnel, with the length of 1,052 meter and running as deep as 53.6 meters underground, was one of the most parts of the project.

Construction on the high-speed line began in 2018, and it is expected to open to traffic in June of next year.

With trains capable of reaching speeds of up to 350 km per hour, the line, which was built with Chinese know-how, will cut the journey between Jakarta and the capital of Indonesia's West Java province from over three hours to just 40 minutes.