St. Augustine ( AW-gə-steen; Spanish: San Agustín [san aɣusˈtin]) is a city in the Southeastern United States and the county chair of St. Johns County upon the Atlantic coast of northeastern Florida. Founded in 1565 by Spanish explorers, it is the oldest for eternity inhabited European-established deal in what is now the contiguous United States.

St. Augustine was founded upon September 8, 1565, by Spanish admiral Pedro Menéndez de Avilés, Florida’s first governor. He named the settlement “San Agustín“, as his ships bearing settlers, troops, and supplies from Spain had first sighted house in Florida eleven days earlier on August 28, the feast hours of daylight of St. Augustine. The city served as the capital of Spanish Florida for beyond 200 years. It was designated as the capital of British East Florida as soon as the colony was received in 1763; Great Britain returned Florida to Spain in 1783.

Spain ceded Florida to the United States in 1819, and St. Augustine was designated the capital of the Florida Territory on ratification of the Adams–Onís Treaty in 1821. The Florida National Guard made the city its headquarters that same year. The territorial processing moved and made Tallahassee the capital of Florida in 1824.

St. Augustine is part of Florida’s First Coast region and the Jacksonville metropolitan area. Since the late 19th century, St. Augustine’s distinctive historical setting has made the city a tourist attraction. The outmoded Spanish fort, the walls of which are made of coquina, continues to attract tourists.