Folly Island is a barrier island

Barrier island

Barrier islands, a coastal landform and a type of barrier system, are relatively narrow strips of sand that parallel the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen...

 in the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

 near Charleston, South Carolina

Charleston, South Carolina

Charleston is the second largest city in the U.S. state of South Carolina. It was made the county seat of Charleston County in 1901 when Charleston County was founded. The city's original name was Charles Towne in 1670, and it moved to its present location from a location on the west bank of the...

. It is one of the Sea Islands

Sea Islands

The Sea Islands are a chain of tidal and barrier islands on the Atlantic Ocean coast of the United States. They number over 100, and are located between the mouths of the Santee and St. Johns Rivers along the coast of the U.S...

 and is within the boundaries of Charleston County, South Carolina

Charleston County, South Carolina

Charleston County is a county located in the U.S. state of South Carolina. According to a 2005 U.S. Census Bureau estimate, its population was 330,368. Its county seat is Charleston. It is the third-most populous county in the state . Charleston County was created in 1901 by an act of the South...

. During the American Civil War

American Civil War

The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

, the 7 square miles (18.1 km²) island served as a major staging area for troops of the Union Army

Union Army

The Union Army was the land force that fought for the Union during the American Civil War. It was also known as the Federal Army, the U.S. Army, the Northern Army and the National Army...

 that were attacking Confederate

Confederate States Army

The Confederate States Army was the army of the Confederate States of America while the Confederacy existed during the American Civil War. On February 8, 1861, delegates from the seven Deep South states which had already declared their secession from the United States of America adopted the...

 forces in the Charleston region. The largest settlement on Folly Island is Folly Beach

Folly Beach, South Carolina

Folly Beach is a city, located on historic Folly Island, in Charleston County, South Carolina, United States. The population was 2,117 at the 2000 census. As defined by the U.S. Office of Management and Budget, and used by the U.S...

.

History

Folly Island was first discovered by English sailors, who named the island after the Old English word "folly," or thickets, from which the term foliage is also derived. The island was a haven for pirates and seafarers in colonial times. It was occupied by the Union army in August 1863 and served as a supply depot and camp for the troops besieging Charleston. Folly Island stayed in Federal control for the rest of the war.