Columbia is a city in Maury County, Tennessee, United States. The 2008 population was 34,402 according to U.S. Census Bureau estimates. It is the county seat of Maury County. The town is notable for being the self-proclaimed "Mule capital of the world" and honors this with Mule Day, a large celebration held annually in April. Columbia is also the home of the national headquarters for the Sons of Confederate Veterans.