Gretna is a city in Gadsden County, Florida, United States. The population was 1,709 at the 2000 census. As of 2004, the population estimated by the U.S. Census Bureau is 1,701 http://www. census. gov/popest/cities/tables/SUB-EST2004-04-12. xls. It is located on U.S. 90 and is about 8 miles south of the Florida-Georgia border. Gretna is part of the Tallahassee, Florida Metropolitan Statistical Area.