Charleston is the oldest and second-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 and Cooper Rivers, or, as is locally expressed, "where the Cooper and Ashley Rivers come together to form the Atlantic Ocean."
Founded in 1670 as Charles Town in honor of King Charles II of England, Charleston adopted its present name in 1783. It moved to its present location on Oyster Point in 1680 from a location on the west bank of the Ashley River known as Albemarle Point. By 1690, Charles Town was the fifth-largest city in North America, and it remained among the 10 largest cities in the United States through the 1840 census. With a 2010 census population of 145,089 (and a 2015 estimate of 152,486), current trends put Charleston as the fastest-growing municipality in South Carolina. The population of the Charleston metropolitan area, comprising Berkeley, Charleston, and Dorchester Counties, was counted by the 2014 estimate at 727,689 – the third-largest in the state – and the 78th-largest metropolitan statistical area in the United States.