A bullet train arrives at Shijiazhuang Railway Station, north China's Hebei Province, Jan. 10, 2016.

China Railway plans to comprehensively implement the new and optimized railway diagram in mid-May, to open 300 pairs of passenger trains and 100 pairs of night bullet trains. This would be the largest incremental adjustment in recent years.

The new operation diagram will see a total of 2,100 pairs of bullet trains out of 3,400 passenger trains. The added red-eye bullet trains will be mainly running among Beijing, east China’s Shanghai, Ningbo, and Hangzhou, south China’s Guangzhou and Shenzhen, and southeast China’s Guizhou.

The adjustment is to meet the surging demands of domestic transportation. Last year, China has 19,000 kilometers of high-speed rail in operation, and the whole railway network carried over 2.5 billion people. The increase in passenger trains is also considered a compensation for the slope China Railway has been suffering in cargo transportation.