Jacksonville is the largest city in the state of Florida and the county seat of Duval County. Since 1968, Jacksonville has been the largest city in land area in the contiguous United States; this resulted from the consolidation of the city and county government, along with a corresponding expansion of the city limits to include almost the entire county.

In 2007, Jacksonville ranked as the United States' twelfth most populous city, with 794,555 residents. It is the principal city in the Greater Jacksonville Metropolitan Area area, a region with a population of 1,277,997, the fourth largest metropolitan area in the state, as of the 2006 Census Bureau estimates. Jacksonville is the third most populated city on the East Coast, after New York City and Philadelphia.

About south of the Georgia border, Jacksonville is in the First Coast region of northeast Florida and is centered on the banks of the St. Johns River. The settlement that became Jacksonville was founded in 1791 as Cowford, because of its location at a narrow point in the river across which cattle were once driven. The city was renamed in 1822 for Andrew Jackson, the first military governor of the Florida Territory and eventual seventh President of the United States.