Jacksonville is the largest city by population in the U.S. state of Florida, the 12th most populous city in the United States and the largest city by area in the contiguous United States. It is the county seat of Duval County, with which the city government consolidated in 1968.

Jacksonville is in the First Coast region of northeast Florida and is centered on the banks of the St. Johns River, about 25 miles (40 km) south of the Georgia state line and about 340 miles (550 km) north of Miami. The Jacksonville Beaches communities are along the adjacent Atlantic coast. Its riverine location facilitates two United States Navy bases and the Port of Jacksonville, Florida's third largest seaport. Significant factors in the local economy include services such as banking, insurance, healthcare and logistics. A regional business center, it also has many museums and cultural offerings.