Tartaruos, or Tartarus is the deepest part of the Underworld in Greek mythology. It was used as a prison by the ruling order of gods. It is now mainly inhabited by Titans. Former/Current prisoners are * The Cyclopes * The Hecatonchires * The Titans * Ixion * Sisyphus * Tantalus * Salmoneus * The Danaids * Tityus