St. Augustine was founded by Spanish Admiral and conquistador Pedro Menéndez de Avilés, in 1565. The “Castillo de San Marco” (Castle of St. Mark) was built on the Matanzas river, beginning in 1672, to protect both the city and the state of Florida from various possible invaders. It is the oldest masonry fort in the continental United States, and today is a major tourist attraction. My wife and I have been there many times, and count St. Augustine as one of our favorite nearby weekend vacation spots.