Castillo de San Marcos National Monument
![Castillo de San Marcos in St. Augustine Castillo de San Marcos in St. Augustine](https://www.crestonhousefl.com/sites/nchf/files/styles/750x500/public/images/event/GettyImages-535297479.jpg)
The oldest masonry fortification in the contintental United States, Castillo de San Marcos National Monument was built over 450 years ago by the Spanish. Offering self-led tours with an app, weapon demonstrations, and rangers in period dress, this park will have you feeling like you have stepped back in time!