Two hours from Beijing, and worth an overnight rather than a day trip

High-speed trains from Beijing North reach Datong South in about two hours, which tempts people into a day return. That leaves time for Yungang and nothing else.

Stay a night inside the rebuilt old town instead: the Huayan and Shanhua monasteries are the real thing, Liao and Jin halls with painted clay figures, and they are calm in the early evening. Then the Hanging Temple and Yingxian fill the next day before an afternoon train onward to Pingyao or back.