About Castillo De San Marcos National Monument
Built by the Spanish in St. Augustine to defend Florida and the Atlantic trade route, Castillo de San Marcos National Monument preserves the oldest masonry fortification in the continental United States and interprets more than 450 years of cultural intersections.
Things to do
Historic & cultural site
When to go
JanFebMarAprMayJunJulAugSepOctNovDec
Best Mar–OctAverage low–high: 68–76°FAverage monthly sunny share of daylight: 53%6.5 wet days / month
Weather data & source
Each figure averages the highlighted months. 2018–2023 averages, not a forecast. Wet days estimate days with at least 1 mm of rain or snow using a calibrated ERA5 threshold. Contains modified Copernicus Climate Change Service information. Weather data by Open-Meteo.com (AWS Open Data, CC BY 4.0). ERA5 via Open-Meteo AWS Open Data
Plan your visit
Castillo De San Marcos National Monument is managed by National Park Service. Check current conditions, permits, and reservations before you go.
See it on Recreation.gov →