Great Falls is the third-largest city in the U.S. state of Montana and the county seat of Cascade County. The population was 58,505 according to the 2010 census, and was estimated at 58,434 on July 1, 2019. The city covers an area of 22.9 square miles and is the principal city of the Great Falls, Montana, Metropolitan Statistical Area, which encompasses all of Cascade County. The county’s population stood at 81,327 in the 2010 census.
A cultural, commercial and financial center in the central part of the state, Great Falls is located just east of the Rocky Mountains and is bisected by the Missouri River. It is 180 miles from the east entrance to Glacier National Park in northern Montana, and 264 miles from Yellowstone National Park in southern Montana and northern Wyoming. A north–south federal highway, Interstate 15, serves the city.
Great Falls is named for a series of five waterfalls located on the Missouri River north and east of the city. The Lewis and Clark Expedition of 1805–1806 was forced to portage around a 10-mile stretch of the river in order to bypass the falls; the company spent 31 days in the area, performing arduous labor to make the portage.