One of the best and most interactive historical experiences you can have in St. Augustine is visiting Castillo de San Marcos National Monument. It’s the only existing 17th century military construction in the United States, and its oldest masonry fort. San Marcos is designed in the Bastion System, of 15th century Italian origin, angular and star shaped.
The most easily accessible natural resource to build the fort in Florida was coquina stone, light and porous. You would think that this wouldn’t be a great material to use for a fort, but it’s air pockets made it compressible and cannonballs were absorbed into the wall rather than shattering it.
Walking up on the walls there is an incredible view,
including the St. Augustine Lighthouse.
Inside there are many examples of 18th century Spanish cannons and mortars.
The fort successfully held through two sieges by the English in the 1700s. While the structure was steadfast, in Europe a treaty was signed during the Seven Years War passing Florida over to Britain in 1763 – in exchange for its other more strategic colonies of Cuba and Philippines back. You can walk into a replica British-era bunk.
Again, the fort would pass hands of which it remains today, and the United States would rename it Fort Marion. It would hold captive Native Americans during the Seminole Wars. Later during the Civil War Confederates took hold of the fort, but deemed the war would end quickly and never reach as far south as Florida. Artillery was sent to other tactical locations and the fort was all but abandoned when in 1862 Union forces arrived and maintained the area until the end of the war.
There is so much to learn through the interesting interactive informational plaques, walking in the rooms, through events, and in the visitors center. Visiting the fort is $10.00 and tickets are good for 7 days. Children 15 and under are free, as are America the Beautiful pass holders.