Eddyville is a city in Lyon County, Kentucky, United States. The population was 2,350 at the 2000 census. It is the county seat of Lyon County . The Kentucky State Penitentiary is located in Eddyville.
Eddyville, the seat of Lyon county, was settled around 1798 and named for the eddies in the nearby Cumberland River. It became the seat of Livingston County when it was formed in 1799, later the seat of Caldwell County in 1809, and finally the seat of Lyon County when it was formed in 1854. Thus, it holds the distinction of being the only city in Kentucky to have served as the county seat of three separate counties. The Eddyville post office opened in 1801.
Throughout Kentucky, Eddyville is best known as a synonym for the Kentucky State Penitentiary, although the prison itself is actually 3 miles (5 km) south of the present town, on the shore of Lake Barkley in Old Eddyville on KY 730. Taking six years to build (1884–1890), the massive stone prison structure towers over Lake Barkley, and is sometimes called "The Castle on the Cumberland." Its electric chair has had a long history of use, with its use dating to the period before 1936 when public executions were still conducted in Kentucky for punishment for some crimes (e.g., rape, see for example Rainey Bethea), with electrocutions at Eddyville being strictly reserved for capital punishment for conviction of other crimes (e.g., murder). Executions are still held at the prison, although there have only been three since 1976 (and only one since 1999) and the primary method has been changed to lethal injection.