Jacksonville is the most populous city in the U.S. state of Florida and the largest city by area in the contiguous United States. 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. With an estimated population of 907,529 as of 2017, Jacksonville is also the most populous city in the southeastern United States. The Jacksonville metropolitan area has a population of 1,626,611 and is the fourth largest in Florida.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 340 miles north of Miami. The Jacksonville Beaches communities are along the adjacent Atlantic coast.