The D4667 train departed from Baotou Railway Station at 10:08 am on Dec 23, marking the opening of the Baotou–Huinong section of the Baotou–Yinchuan High-speed Railway (HSR) and the full operation of the HSR.

The line connects Baotou city in North China's Inner Mongolia autonomous region and Yinchuan city in Northwest China's Ningxia Hui autonomous region.

It spans 519 kilometers, has a design speed of 250 kilometers per hour, and includes 13 stations. Travel time between Baotou and Yinchuan has been cut from about six hours to under three.

The railway is a crucial component of the Beijing-Lanzhou corridor, a main channel within China's "eight vertical and eight horizontal" high-speed railway network. Its full operation creates a faster northwestern route to Beijing and further enhances the national rail network and connectivity in northwest China.