HARBIN, Nov. 18 (Xinhua) -- A new high-speed railway line started trial operation on Sunday in northeastern China, linking the cities of Harbin and Mudanjiang in Heilongjiang Province.

The 293-km line, built in a region where the temperature can be as low as minus 40 degrees Celsius in winter, is designed to allow trains to run at 250 km per hour, cutting the travel time to two hours from over four hours, according to the China Railway Harbin Group.

The railway line is expected to start operation by the end of the year.

Construction of the railway line started in December 2014 as one of the key projects in China's high-speed rail network scheme.

China's railway network is expected to hit 175,000 km in length by 2025, compared with 127,000 km of operating tracks by the end of last year.