The county in which Sun River Montana is located is ranked as the what most populous county in Montana?
Sun River, Montana Sun River is a census-designated place (CDP) in Cascade County, Montana, United States. The population was 124 at the 2010 census. It is part of the Great Falls, Montana Metropolitan Statistical Area.
Poplar, Montana Poplar is a city in Roosevelt County, Montana, United States. The population was 810 at the 2010 census.