• 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 »

Operating Hours & Seasons

The Castillo de San Marcos is open to the public from 8:45 AM to 5:15 pm every day of the year except December 25. (The ticket booth closes at 5:00 pm.) The Park grounds are closed from midnight until 5:30 am.

Visitation is lowest from the middle of September through late November.

Visitation is highest June through Labor Day, and quite high on summer and holiday weekends when an average of 3500 people visit the Castillo daily.

School group visitation is quite high February through May. High visitation can also be expected during the December holidays.

Did You Know?

Bronze Spanish cannons look out over the city of St. Augustine

Black, or gun, powder is a mix of potassium nitrate, sulfur, and charcoal used as a propellant charge in cannons. Burning rapidly when ignited, it expands 600 times its volume creating pressures that can hurl a cannonball up to 3.5 miles! Castillo de San Marcos National Monument, Florida