Located in FL.
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.
Use this page to check live NPS alerts, weather, things to do, events, fees, campgrounds, and build a day-by-day itinerary with Trailie.
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Open daily · 9:00AM - 5:00PM
$15.00
Entrance - Per Person
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Tell Trailie your dates, pace, and interests — get a day-by-day Castillo de San Marcos National Monument plan with hikes, drives, and must-see stops.
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Fee Stations are only accepting credit cards for the purchase of entry tickets and passes.
Common questions
The summary above covers timing and highlights. These go deeper on reservations, crowds, and logistics — check Alerts and Permits for live updates.
TrailVerse lists 4 reservation types on the Permits tab, including Castillo de San Marcos National Monument Tours and Academic Teacher-Guided Tour. Recreation.gov listings can change seasonally — confirm current rules before you set dates.