A Dive into the Castillo de San Marcos

If you have been to St. Augustine, you have seen the Castillo de San Marcos. Sitting on a hill in the middle of the historic district, it is nearly impossible to miss. But how much do you really know about the ancient city’s oldest complete structure?

Construction by the Spanish

Construction of the Castillo de San Marcos began in 1672, after several attacks burned the city's wooden forts. To keep St. Augustine afloat, a stronger and more long-term fort had to be constructed. 

The Castillo de San Marcos’ unique star-shape is an example of Spanish fortification during this era of conquest. Its shape is not accidental; it is mathematical. The 1600s brought changes to warfare, and the Spanish had to keep up with the competition. This is how the “Vauban fortification” style of the Castillo de San Marcos was born. This wasn't the only fort built in this shape, but it is the best example of the style in the United States. Its success relies heavily on geometry, and the structure's centuries-long strength proves the math was correct.

The next time you are in St. Augustine, take some time to appreciate the spectacle that is the Castillo de San Marcos. The construction is a work of genius, and a big reason we can all enjoy St. Augustine today. 

The Impact of Coquina

Wondering what the fort is made of to give it such a distinctive look? That’s coquina! It is a sedimentary rock that forms in just a few places around the world. The biggest collection is right here in St. Augustine! It forms from thousands of tiny shell fragments and appears in piles along the eastern Florida shore. The batch used to build the fort was quarried right across the intracoastal on Anastasia Island. Take some time to explore Anastasia State Park during your next trip to the oldest city to see where the Spanish first found St. Augustine’s iconic building material.

The strength of the fort’s coquina was put to the test in 1702. English troops, headed by James Moore, governor of South Carolina, attacked St. Augustine and its new fort for nearly two months. When the English finally retreated, the city was burning, but the structure still held. This kept the city from being captured by English forces, and the strength of the Castillo de San Marcos proved itself time and time again. St. Augustine was never taken over by force, thanks to the coquina-built fort watching over its town. 

The Spanish quickly realized coquina was the best option for the growing city of St. Augustine. Today, many buildings and homes around the historic district are made of the material. Its ability to withstand attacks, the elements, and hundreds of years of wear and tear has proven the Spanish right. 

Be sure to venture over to Aviles Street and the surrounding area, because many surviving coquina buildings can be found here! Many can be seen quietly tucked away from the hustle and bustle of the rest of the city. 

How Can I Learn More?

The Castillo de San Marcos is open daily from 9 am to 5 pm, except Thanksgiving Day and Christmas Day. Tickets can be purchased on the National Park System’s website or on-site during your visit to St. Augustine.

Purchasing a ticket through the National Park Service is the only way to enter the fort, which is highly recommended. Park rangers are around and happy to answer your questions or discuss what's happening at the fort. In addition, reenactors will teach you about life in St. Augustine during the time the fort was active. These conversations with the people who make the Castillo de San Marcos great will be memories your family remembers forever. 

For a more well-rounded experience, take a historical tour with Pineapple Ride & Tour. Expert local guides will explain why the Castillo de San Marcos was built, why it mattered, and how it ultimately shaped the landscape of St. Augustine. 

Pineapple Ride & Tour offers numerous options to fit your needs. They even offer private tours! Bring up to 10 people and enjoy some time around the oldest city. Pineapple Ride & Tour is also the only locally owned tour company in town to offer free on-site parking. They guarantee a convenient, stress-free day in St. Augustine for all guests.

Looking for something more spooky? They can do that, too! The Haunted Truth Tour operates Wednesday through Sunday and brings guests closer to St. Augustine’s dark history. Considering the centuries of stories that come from the Castillo de San Marcos, it is no surprise that this is just one of the stops on their haunted tour.