Fort Matanzas National Monument

Fort Matanzas was built by the Spaniards to guard the Matanzas Inlet and River which was the back door to St. Augustine as shown in the park brochure.

When the United States took possession of the fort in 1821 only three Spanish soldiers were there. The interior was in ruins, and the gun platform’s east wall and its foundation were cracked. The U.S. Army sent an inspector who reported that the fort was obsolete and had only historical value. Although owned by the War Department, Fort Matanzas was never occupied by the US army. Florida was the third state to vote for secession on January 10, 1861. Confederate troops immediately took Fort Marion (Castillo de San Marcos) from the lone Union sergeant caretaker who asked for a receipt and travel money to get home. Believing the war would be short and not venture this far south, the Confederates removed the cannons from Fort Marion and sent them to more strategic areas. In March 1862, the Union Navy arrived off the coast of St. Augustine. With no guns for defense, Fort Marion was abandoned, and Union forces occupied it. The St. Augustine area remained in Federal hands for the remainder of the war. With the St. Johns River heavily patrolled, Confederate blockade runners attempted to use the Matanzas Inlet during the War, but the Union army stationed a barge in the river near the fort’s ruins to prevent that.