Fort Sumter is a sea fort built on an artificial island protecting Charleston, South Carolina, from naval invasion. Its origin dates to the War of 1812 when the British invaded Washington by sea. It was still incomplete in 1861 when the Battle of Fort Sumter began the American Civil War. It was severely damaged during the war, left in ruins, and although there was some rebuilding, the fort as conceived was never completed.
Since the middle of the 20th century, Fort Sumter has been open to the public as part of the Fort Sumter and Fort Moultrie National Historical Park, operated by the National Park Service.