Jacksonville is the most populous city in Florida, and is the largest city by area in the contiguous United States as of 2020. It is the seat of Duval County, with which the city government consolidated in 1968. Consolidation gave Jacksonville its great size and placed most of its metropolitan population within the city limits. As of 2020, Jacksonville's population is 949,611, making it the 12th most populous city in the U.S., the most populous city in the Southeast, and the most populous city in the South outside of the state of Texas. With a population of 1,605,848, the Jacksonville metropolitan area ranks as Florida's fourth-largest metropolitan region.
Jacksonville is centered on the banks of the St. Johns River in the First Coast region of northeast Florida, about 25 miles south of the Georgia state line and 328 miles north of Miami. The Jacksonville Beaches communities are along the adjacent Atlantic coast. The area was originally inhabited by the Timucua people, and in 1564 was the site of the French colony of Fort Caroline, one of the earliest European settlements in what is now the continental United States.