The foundations of the citadel date from the Phoenician times. In the Middle Ages a castle was built on it to protect the population of Gozo from pirates and invaders. Even so, slave hunters abducted most of Gozo's residents. After the Knights of St. John came to Gozo from Jerusalem in the 16th century, they built today's citadel. It is now uninhabited. Today the old prison is located here in the courtyard, today a museum, the seat of the Bishop of Gozo and Comino, souvenir shops and a restaurant.