Report, if you have a problem with this page“ Descending south into St. Augustine’s Historic District along A1A, visitors are immediately confronted by an edifice which serves as a stark reminder that the city was originally founded as a military outpost, deep in hostile territory. Jutting up like a molar from the defensive teeth of the Ancient City is the forbidding fortress of Castillo de San Marcos, a coquina fortification which has served many roles it its nearly three hundred fifty year history. ”