This fort changed hands five times. From 1565 to1763 it was held by the Spanish, and again from 1784 to 1821. The British period was from 1763 to1784. The Confederacy held it for 1 year, from 1861 to1862, and the United States held it from 1821 to the present. Construction started in 1672, making it the oldest masonry fortification in the U.S.

The fort stands in the middle of town next to the water. From a distance it looks quite massive. And up close it really is. There is considerable walking on this tour, which include steps. Tours are available at the fort, or you can walk it yourself using the brochures as your guide. There are cannons up top overlooking the water, where you will get a beautiful view of the area. Below, you go in and out of rooms that are hot, especially during the afternoon in the summer. The tour guide will give you the history of each room.

For the history buff this is probably quite interesting and unusual. But for someone whose interest in history is remembering what he or she had for lunch yesterday, this might not be the place for you. If you do go, I strongly suggest that you don’t visit the fort at the end of the day. It didn’t really have anything that held my interest, so my enthusiasm wasn’t too strong and all the walking seemed like miles. I wouldn’t suggest this attraction for most young children.

For a mere $4, though, I recommend taking a more in depth look at this wonderfully preserved example of colonial architecture. I mean, one normally has to go to Latin America to see this sort of thing. It's a national monument for a reason.

I've seen my fair share of historical forts and the Castillo de San Marcos ranks highly among them. It is certainly a unique specimen in the United States. Aside from the historic value, the Castillo provides some excellent views that you won't get elsewhere. The view of Old Town from atop the fortress walls is very picturesque and looking out toward Matanzas Bay near the end of day can be a truly beautiful sight. So, whether for a little trip back in time, or for the aesthetic rewards, take the opportunity to climb atop this old sentinel of St. Augustine.

The fort was built in the 17th century by the Spanish and has changed hands multiple times over the years. Listen to a ranger-led program or walk the battlements on your own. There are great views from the top and some good photo ops with cannons and turrets. There is also a small gift shop.