In 1847, at the end of the Second Seminole War, the Federal government started construction of a brick fort, later named Fort Clinch. It was captured by the Confederate army in 1861, but it was abandoned in order to send soldiers to other more critical areas. Federal troops occupied the fort for the remainder of the war and through the 1860s. The fort was unused until the Spanish-American war in 1898, but then was vacated again and it slowly deteriorated. During the Great Depression, Civilian Conservation Corps workers began restoring the fort to its Civil War appearance. The State of Florida purchased the peninsula to create a state park, which opened in 1938. The fort was listed in the National Register of Historic Places in 1972.
Fort Clinch is in a location that is highly vulnerable to the elements. It sits at the mouth of the St. Marys River on a beach front location. The peninsula is windy most of the time, so the fort is constantly blasted with sand. Sand, water, excessive heat and time have taken their toll on the fort, and in particular the bastions. SPS restored the bastions, which project from the fort walls and contain mounts for cannons. We removed rusted steel, which had caused substantial damage to the walls and the openings and built or re-pointed parts of the walls and openings.