Cadiz is a home rule-class city in and the county seat of Trigg County, Kentucky, United States. The population was 2,558 at the 2010 census. It is part of the Clarksville metropolitan area.Cadiz is an old town located close to the Land Between the Lakes, a popular recreation area, and was a base of Union and Confederate operations during the Civil War. It permits the sale of alcoholic beverages.