Their web site states:
“In 1855 some of South Carolina’s most distinguished citizens came together to record and preserve the past-for the sake of the future. Motivating them was the fear that if they did not act, South Carolina’s rich historical legacy would be lost to future generations. They founded the South Carolina Historical Society, which today is the state’s oldest and largest private repository of books, letters, journals, maps, drawings, and photographs about South Carolina history. The mandate of our founders remains our mission today: “to collect information respecting every portion of our state, to preserve it, and when deemed advisable, to publish it.” The Society’s holdings, located in the historic Robert Mills Fireproof Building in Charleston, S.C., are vast and grow constantly with the addition of materials from 200 years ago and from two weeks ago. It is especially rich on South Carolina’s colonial and antebellum eras and the American Civil War. The Society is a private, non-profit organization depending entirely on the generosity of its members to preserve and extend awareness of South Carolina history. We receive no local, state, or federal funding for our operations.”
Don’t expect to take pictures. The staff are very helpful.
We did some research in there recently and found that one visit gathered more information than several years of research done by distance.