Grand Junction is a home rule municipality that is the county seat and the most populous municipality of Mesa County, Colorado, United States. The city has a council–manager form of government, and is the most populous municipality in all of western Colorado. Grand Junction is 247 miles (398 km) west-southwest of the Colorado State Capitol in Denver. As of the 2010 census, the city's population was 58,566. Grand Junction is the 15th most populous city in the state of Colorado and the most populous city on the Colorado Western Slope. It is a major commercial and transportation hub within the large area between the Green River and the Continental Divide. It is the principal city of the Grand Junction Metropolitan Statistical Area, which had a population of 146,723 in 2010 census.
The city is along the Colorado River, at its confluence with the Gunnison River, which comes in from the south. "Grand" refers to the historical Grand River; it was renamed the Upper Colorado River in 1921. "Junction" refers to the confluence of the Colorado and Gunnison rivers. Grand Junction has been nicknamed "River City"