How Crowded Is Castillo de San Marcos in October?
October is a quiet month at Castillo de San Marcos National Monument, running about 0.6× the park's average month — roughly 5% of the year's visitors come in October. That puts it between the March peak and the September low. Overall our best-time score rates October as "Excellent" for a visit. Typical October weather averages a high near 82°F and a low around 67°F, with about 4.4" of precipitation. You'll get about 11.3 hours of daylight to explore.
Frequently Asked Questions
October is quiet at Castillo de San Marcos National Monument (about 0.6× the average month). Our best-time score rates it "Excellent". The single best month overall is October.
The busiest month is March and the quietest is September. October sits at about 0.6× the park's average, or 5% of annual visitation.
Source: National Park Service Visitor Use Statistics (1979–2025), NOAA NCEI Climate Normals 1991–2020. Updated 2026-06-20.