• 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?

Coquina is a mixture of broken shell sand and calcium, making it nature's version of concrete

The word coquina means "tiny shell" in Spanish. It was the name they gave to the small clam that was abundant on the northeast Florida beaches. It is the predominant shell in the rock also called coquina used to build the Fort. Castillo de San Marcos National Monument, Florida