Columbus is a consolidated city-county located on the west central border of the U.S. state of Georgia. Located on the Chattahoochee River directly across from Phenix City, Alabama, Columbus is the county seat of Muscogee County, with which it officially merged in 1970. Columbus is the third-largest city in Georgia and the fourth-largest metropolitan area. According to the 2017 estimates from the U.S. Census Bureau, Columbus has a population of 194,058 residents, with 303,811 in the Columbus metropolitan area. The metro area joins the nearby Alabama cities of Auburn and Opelika to form the Columbus–Auburn–Opelika Combined Statistical Area, which has a 2017 estimated population of 499,128.
Columbus lies 100 miles (160 km) southwest of Atlanta. Fort Benning, the United States Army's Maneuver Center of Excellence and a major employer, is located south of the city in Chattahoochee County. Columbus is home to museums and tourism sites, including the National Infantry Museum, dedicated to the United States Army's Infantry Branch. It has the longest urban whitewater rafting course in the world constructed on the Chattahoochee River.