Miles City is a city in and the county seat of Custer County, Montana, United States. The population was 8,354 at the 2020 census.

Montana is a landlocked state in the Mountain West subregion of the Western United States. It borders Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, and the Canadian provinces of Alberta, British Columbia, and Saskatchewan to the north. It is the fourth-largest state by area, the eighth-least populous state, and the third-least densely populated state. Its capital is Helena, while the most populous city is Billings. The western half of the state contains numerous mountain ranges, while the eastern half is characterized by western prairie terrain and badlands, with smaller mountain ranges found throughout the state.