Charleston is the oldest and largest city in the U.S. state of South Carolina, the county seat of Charleston County, and the principal city in the Charleston–North Charleston–Summerville Metropolitan Statistical Area. The city lies just south of the geographical midpoint of South Carolina's coastline and is located on Charleston Harbor, an inlet of the Atlantic Ocean formed by the confluence of the Ashley, Cooper, and Wando rivers. Charleston had an estimated population of 134,385 in 2016. The estimated population of the Charleston metropolitan area, comprising Berkeley, Charleston, and Dorchester counties, was 761,155 residents in 2016, the third-largest in the state and the 78th-largest metropolitan statistical area in the United States.Charleston was founded in 1670 as Charles Town, honoring King Charles II of England.