How Crowded Is Castillo de San Marcos in June?
June is an average month at Castillo de San Marcos National Monument, running about 1.0× the park's average month — roughly 8% of the year's visitors come in June. That puts it between the March peak and the September low. Overall our best-time score rates June as "Fair" for a visit. Typical June weather averages a high near 89°F and a low around 72°F, with about 6.3" of precipitation. You'll get about 13.9 hours of daylight to explore.
Frequently Asked Questions
June is average at Castillo de San Marcos National Monument (about 1.0× the average month). Our best-time score rates it "Fair". The single best month overall is October.
The busiest month is March and the quietest is September. June sits at about 1.0× the park's average, or 8% of annual visitation.
Source: National Park Service Visitor Use Statistics (1979–2025), NOAA NCEI Climate Normals 1991–2020. Updated 2026-06-20.