The Castillo de San Marcos was begun in 1672, over a hundred years after Menendez d"Avila first landed and fortified the site of a Timucua Village south of this point.
During the American Revolution it was a British stronghold. It is the oldest masonry fort in the continental United States.
San Marcos was besieged twice but never conquered by force though it changed hands four or five times by treaty.
In the 19th century it was a prison for Native Americans including Osceola and Geronimo's wife.
The prominent, round-top, pigeon-encrusted structure on the right is a garrita or bartizan -- an overhanging, wall-mounted turret projecting from the wall, most frequently at corners. Designed to protect a warder and enable him to see in all directions, they are generally furnished with oylets or arrow slits.
Today you learned three new words.