It lies under the administration of Chengde City, and is the northernmost county of the province, bordering Inner Mongolia to the north.

The area has been historically home to Manchu soldiers, and the local dialect of Mandarin is similar to that of Beijing, though there is some Northeastern influence.

In the early Qing Dynasty, the Auqan, Kharchin and Onnigud Mongols gave these lands as a gift to the Kangxi Emperor, who then created the Mulan Hunting Grounds in Weichang.

Weichang is located in the northernmost part of Hebei, with a latitude range of 41° 35' to 42° 40' N and longitude range of 116° 32' to 118° 14' E. It borders Inner Mongolia's Chifeng city to the east, Hexigten Banner to the north, as well as Duolun County to the northwest.

The coldest temperature recorded in the province was −42.9 °C (−45 °F) on 12 January 1957 at Yudaokou Township (御道口乡).