Columbus is a town in and the county seat of Stillwater County, Montana, United States. The population was 1,748 at the 2000 census.The community originated as a stagecoach station on the Yellowstone River.The original name was Sheep Dip, then changed to Stillwater, but because of a Stillwater, Minnesota on the Northern Pacific RR, the mail presented a problem. Then came the name Columbus, Montana.
According to the United States Census Bureau, the town has a total area of 1.2 square miles (3.1 km2), of which, 1.2 square miles (3.1 km2) of it is land and 0.04 square miles (0.10 km2) of it (3.20%) is water. Columbus is located between the Yellowstone River, the old Yellowstone Trail, Highway 10, and now Interstate 90.