In 1565, King Philip II of Spain commissioned Menéndez to eliminate a French Protestant settlement at Fort Caroline. Menéndez landed on September 8 - the feast day of St. Augustine of Hippo - named the settlement accordingly, then marched north to slaughter the French. The Spanish were thorough; most survivors were executed. St. Augustine became the northernmost outpost of Spanish Florida, defended by wooden forts, sustained by supply ships from Cuba, and constantly threatened by English and Indigenous attacks. The settlement's early decades were precarious; its survival was never guaranteed.

The Castillo de San Marcos, begun in 1672 and completed in 1695, is the oldest masonry fort in the continental United States. Built of coquina - a local stone composed of compressed shells - the walls absorbed cannon fire rather than shattering. The British besieged the fort twice without capturing it. When Florida passed to British control in 1763, the fort became Fort St. Mark. When Spain regained Florida in 1783, the original name returned. The United States acquired Florida in 1821; the fort became Fort Marion. The name Castillo de San Marcos was restored in 1942. The fort survives, solid, patient, older than the nation that now owns it.

St. Augustine languished through much of the 19th century until Henry Flagler arrived. The Standard Oil co-founder built luxury hotels, extended his railroad, and transformed the old Spanish town into a winter resort for wealthy Northerners. The Ponce de León Hotel (now Flagler College) and the Alcazar (now the Lightner Museum) established St. Augustine as a destination. The historic Spanish quarter became an attraction rather than a liability. The city that had been founded to kill Protestants became a playground for Protestant industrialists.

Modern St. Augustine runs on history tourism. The historic district preserves Spanish colonial architecture, narrow streets, and coquina buildings. Attractions range from serious (the Castillo, the Cathedral Basilica) to kitschy (the Fountain of Youth Archaeological Park, various ghost tours). The city hosts roughly 6 million visitors annually, most concentrated in the walkable downtown. The tourism has preserved what development might have destroyed; the historic buildings survive because they generate revenue. Whether the commercialization cheapens the history or enables its survival depends on perspective.

St. Augustine is located on Florida's northeast coast, roughly 40 miles south of Jacksonville. The historic district is compact and walkable; parking is limited and expensive. The Castillo de San Marcos is operated by the National Park Service; admission is charged. St. George Street is the main pedestrian thoroughfare, lined with shops and restaurants. The Lightner Museum (decorative arts) and Flagler College tours interpret the Gilded Age legacy. The Old Jail, ghost tours, and Ripley's provide entertainment. The beach is east of the historic district. Jacksonville has the nearest major airport. Hotels range from historic B&Bs to chain properties. Visit spring or fall for optimal weather.