Fort Frederick Heritage Preserve in Port Royal, South Carolina, protects the archaeological remains of Fort Frederick, or Fort Prince Frederick, a small British colonial fort built between 1730 and 1734 to help defend against a possible attack from Spanish Saint Augustine, Florida. On the Beaufort River, it guarded the river approach with a battery and cannon and at times housed provincial scout boats. Built of tabby and believed to be South Carolina’s oldest tabby structure, the fort contained barracks and a magazine and was first garrisoned by British regulars until 1736. The site was added to the National Register of Historic Places in 1974 and opened to the public in 2021.