Choibalsan (Mongolian: Чойбалсан) is the fourth-largest city in Mongolia. The name of the city was Bayan Tümen (Баян Түмэн) until 1941, when it was renamed after the communist leader Khorloogiin Choibalsan. It is the capital of the aimag (province) of Dornod and city administrative unit official name is Kherlen sum with area of 281 km2.
It is situated at the Kherlen River, at an elevation of 747 m above sea.
The location has been a post on a trading route for centuries. In the 19th century it grew into a city, and became the economic hub of eastern Mongolia in the twentieth century. After democratization 1992, when the Russian workers left, large parts of the economy collapsed. Since then, the city suffers from one of the highest unemployment rates in Mongolia.
The Choibalsan city has a population of 45,490(1994), 41,714 (2000), 36,142 (2003), 39,500 (2006), 39,500 (2007, 53.2% aimag's population).
Choibalsan is inhabited primarily by Khalkha Mongolians, with smaller numbers of Buryats, Barga, and Üzemchin. There's also a minority of immigrants from Inner Mongolia in China.
The Choibalsan Airport
(COQ/ZMCD) has one paved runway, and is served by regular flights to Ulan Bator