Charleston County, South Carolina

Charleston County is a county in the U.S. state of South Carolina. As of the 2010 census, 350,209 people lived there, making it the third-most populous county in South Carolina (after Greenville and Richland counties). Its county seat is Charleston. The county was formed in 1901.
Geography.
According to the U.S. Census Bureau, the county has a total area of , of which is land and (33%) is water. It is the largest county in South Carolina by total land and water area. It is along the Atlantic coast.