Castillo de San Marcos National Monument

The Castillo de San Marcos stands as a stone fortress constructed from coquina rock, featuring four diamond-shaped bastions and a surrounding moat system.

Spanish engineers began building this military structure in 1672 to protect St. Augustine after multiple attacks, completing the fortification in 1695.

The fortress walls have witnessed exchanges between Spanish, British, and American forces, while also serving as a prison for Native American leaders.

The National Park Service maintains daily guided tours, weapon demonstrations, and educational programs throughout the year with varying seasonal schedules.

The fort's coquina walls absorbed enemy cannonballs instead of cracking, making conventional artillery attacks ineffective against this limestone-shell construction.

Location: Saint Johns County

Operator: National Park Service

Website: https://nps.gov/casa

GPS coordinates: 29.89743,-81.31185

Latest update: March 6, 2025 19:50