Reputedly Ireland's most haunted castle, Leap Castle in Coolderry, County Offaly, dates back to 1250.
Built within a cave mouth in south-central Slovenia, Predjama Castle was the seat of a notorious knight called Erasmus of Lueg.
Commonly known outside Transylvania as Dracula's Castle, the medieval-era Bran Castle has only loose associations with the notorious individual known as Vlad the Impaler.
Edinburgh's landmark 12th-century castle is one of Scotland's most popular tourist attractions.
Carini Castle near Palermo in Sicily is said to be haunted by Laura Lanza, the Baroness of Carini. In 1563, she was discovered in flagrante with her lover.
Moosham Castle near Unternberg in the Lungau region of Salzburg was the site of the Zaubererjackl witch trials between 1675 and 1690.
Medieval Chillingham Castle sends shivers down the spines of many who visit this austere-looking stronghold, said to be the most haunted castle in Britain.
Furthermore, the castle was home to Johann Konrad Dippel, an alchemist who created all sorts of weird potions and elixirs.
Located near the village of Blatce, Houska Castle is traditionally known in folklore as covering one of the gateways to Hell to prevent demons escaping and tormenting humanity.
Dragsholm Castle in Zealand is one of the oldest secular buildings in Denmark, completed in 1215.