The Castillo De San Marcos is the oldest masonry fort in the continental United States. It was built to protect and defend Spain's claim in the New World. It is the oldest structure in St. Augustine - 315 years old - and is a National Monument. Construction on the fort began in 1672 and took 23 years to complete. It is made of coquina and was fire resistant and inpenetrable to enemy attack.

Plan to tour the fort that overlooks the sea on the coast of St Augustine. You will be led through the numerous rooms that were once home to soldiers and prisoners. Throughout the day, Park Rangers give talks, answer questions and a video is show every hour detailing the Castillo's history. Re-enactors in period dress give historical weapons demonstrations on weekends. If you are walking around downtown and hear a canon being fired, this is where the sound is coming from.

1 Castillo Drive

Open daily except Thanksgiving and Christmas Day