Fort Palmetto was a circular fortification of tabby construction believed constructed for the War of 1812. The fort was built on Coles Island, between Folly and Kiawah Islands, and designed to command the Stono Inlet and the entrance to the Folly and Stono Rivers.

In 1861, Confederate troops established seven batteries on Coles Island, oddly numbered Battery # 4 – Battery #9. Fort Palmetto was Battery #7. In a controversial move in March 1862, General Pemberton chose to abandon these batteries, moving their artillery pieces to more defensible positions further inland in the direction of Charleston and out of range of the guns of the Federal gunboats. Confederates removed sixteen pieces of heavy artillery from all batteries at Coles Island. Federal Troops soon occupied the Island and remained there until 1865.

Much of Coles Island was destroyed in the hurricane of 1911, leaving Fort Palmetto standing in the marsh just south of the remnants of the island. The tall tabby walls are still extant, though they have collapsed into the surrounding marsh. The Fort Palmetto site is preserved by the South Carolina Battleground Preservation Trust through a permit issued in 1992 by the South Carolina Coastal Council. The site is accessible only by boat at high tide. The remnants of the circular tabby wall are only visible at low tide.