The Harbin-Dalian High-Speed Railway, the world's first high-speed railway operated at high latitudes and low temperatures, has now been in service for six years.

The 921-kilometer line linking Harbin, capital of China's northernmost province of Heilongjiang, and the port city of Dalian, Liaoning province, travels through the three provinces in Northeast China where temperature drops to as low as -40 C in winter and hits highs of 30 C in summer.

Since the line opened on Dec 1, 2012, over 410,000 trains have run on this track. On Oct 7, the railway handled 208,000 passengers, creating a new record for passenger flow in a single day this year.

Over the past six-year period, it has also withstood as many as 152 snowstorms and proved to be safe and reliable.

The high-speed link reduces the travel time between Harbin and Dalian to four hours from the previous 10 hours.

Joining the Shenyang-Dandong, Dandong-Dalian high-speed railways in the south, the Harbin-Qiqihar, Harbin-Mudanjiang, Harbin-Jiamusi high-speed railways in the north, and the Qinhuangdao-Shenyang high-speed railway in the center, the Harbin-Dalian high-speed railway links cities in Northeast China.

Passengers are able to travel among the central cities in Northeast China, such as Shenyang, Changchun and Dalian, within two hours, while the journey from the major cities in the region to Beijing takes no more than six hours.

The top speed of the bullet trains on the Harbin-Dalian line is 350 kilometers per hour, but in the initial stages of operation, they traveled at reduced speeds. During the line's winter schedule, normally from December to April, trains traveled at 200 km/h, and for the rest of the year, 300 km/h.

Because the line has operated safely for a long period of time, the speed of the trains traveling on the line has been increased to 300 km/h all year round.

Currently, a total of 109 bullet trains travel on the line, providing an average of 140,000 seats each day.

The Harbin-Dalian high-speed railway is playing an important role in boosting the development of transportation, economy and trade in the region.