Columbia County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 67,295. Its county seat is Bloomsburg. The county was created on March 22, 1813, from part of Northumberland County and named for Columbia, a poetic name for the United States that alludes to Christopher Columbus.Columbia County is part of the Bloomsburg-Berwick, PA Metropolitan Statistical Area.GeographyAccording to the U.S. Census Bureau, the county has a total area of, of which is land and (1.4%) is water. The southern tip of Columbia County is part of the Coal Region. The area of the county from the Susquehanna River south to several miles south of Numidia is mostly farmland and state game lands. Around the Susquehanna River, there are several communities, such as Bloomsburg and Catawissa. From the Susquehanna River north as far as Waller, the county is mostly farmland with several patches of forest. North of Waller, the county is mostly state game lands and mountains.