Downtown Jacksonville is the historic core and central business district (CBD) of Jacksonville, Florida. It comprises the earliest area of the city to be developed and is located in its geographic center along the narrowing point of the St. Johns River.

Jacksonville is the most populous city proper in the U.S. state of Florida, located on the Atlantic coast of northeastern Florida. It is the seat of Duval County, with which the City of Jacksonville consolidated in 1968. It is the largest city by area in the contiguous United States as of 2020.