Richmond County, Georgia is 4.4 times larger than North Charleston, South Carolina.
Area: 194 km2 calculated
North Charleston is the third largest city in the U.S. state of South Carolina, with incorporated areas in Berkeley, Charleston, and Dorchester counties. On June 12, 1972, the city of North Charleston incorporated and was the ninth largest city in South Carolina. Wikipedia
Area: 850 km2 calculated
Richmond County is a county located in the U.S. state of Georgia. As of the 2010 census, the population was 200,549. It is one of the original counties of Georgia, created February 5, 1777. Following an election in 1995, the city of Augusta consolidated governments with Richmond County. Wikipedia