• Cannon firing on the gundeck of the Castillo de San Marcos

    Castillo De San Marcos

    National Monument Florida

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  • Summer Weather

    Afternoon Thunderstorms can create dangerous amounts of lightning strikes. If Lightning is visible from the Castillo, Gundeck closures will take place. Click this link for the local weather forcast. More »

Plan A Field Trip

Effective October 1st, 2013 Castillo de San Marcos NM has updated its Academic Fee Waiver process.

If you tour the Castillo de San Marcos NM with a Commercial Tour Guide you do not qualify for an Educational Fee Waiver.


For an Academic Fee Waiver form click here.


For the National Park Service Guidlines on Academic Fee Waivers click here.


While your group is visiting the Castillo de San Marcos NM, we ask that you follow these rules. Click here


If you have any questions please call 904-829-6506, x239 or e-mail us.

Did You Know?

Castillo casemate, or room, which was primarily used for storage.

The Castillo de San Marcos is built with the unique limestone, "coquina". Made of many tiny shell fragments and sand lightly bound together with calcite, it has survived cannon balls and hurricanes but is very fragile to human contact. Castillo de San Marcos National Monument, Florida