• 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 »

America Begins Here

A monument not only of stone and mortar but of human determination and endurance, the Castillo de San Marcos symbolizes the clash between cultures which ultimately resulted in our uniquely unified nation.  Still resonant with the struggles of an earlier time, these original walls provide tangible evidence of America’s grim but remarkable history.

Did You Know?

1642 map showing the ancient coast of florida

The Castillo de San Marcos was originally constructed to defend Florida against pirates hunting the Spanish treasure fleets traveling along the Gulf Stream. Castillo de San Marcos National Monument, Florida