HARBIN, Nov. 30 (Xinhua) -- The track-laying work of a new railway linking the cities of Mudanjiang and Jiamusi in northeast China's Heilongjiang Province reached completion on Monday, local authorities said.

With a designed speed of 250 km per hour, the 370 km high-speed rail line passes through more than 30 tunnels and 100-plus bridges in extremely cold areas, according to the China Railway Harbin Group Co., Ltd.

The construction of the Mudanjiang-Jiamusi high-speed railway, one of the major projects on China's medium- and long-term rail development blueprint, started in 2016. It covered a region often hit by blizzards with temperatures as low as 30 degrees Celsius below zero.

Construction workers have overcome the challenges and completed the track-laying operation 23 days in advance.

China's railway network had a total length of 141,400 km by the end of July, among which 36,000 km were high-speed railways, according to the national railway operator. Enditem