Jacksonville, Florida is 12 times larger than Richmond, Virginia.
Area: 1,988 km2 calculated
Jacksonville is the largest city in the U.S. state of Florida by population 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. Wikipedia
Area: 162 km2 calculated
Richmond is the capital of the Commonwealth of Virginia, in the United States. It is the center of the Richmond Metropolitan Statistical Area and the Greater Richmond Region; since 1871 Richmond has been an independent city. Wikipedia