Bayan Nur, also known as Bayannao'er, is a prefecture-level city located in the western region of Inner Mongolia within the People's Republic of China. The administrative area underwent a formal designation change on December 1, 2003, when it transitioned from being known as Bayannur League to its current status as a prefecture-level city.
Situated in the western portion of the Inner Mongolia Autonomous Region, the city serves as a primary administrative center for its surrounding territory. It is defined by its geographical location within the vast Mongolian plateau and its historical development from a league structure into a modern prefecture-level municipality.