Mategriffon or Matagrifone or Mathegriffon or Rocca Guelfonia was a medieval castle in Messina, Sicily, located in what is today Viale Principe Umberto. Its strategic position upon a rocky hill close to the historic city centre gave a commanding view of the harbour and Strait of Messina. In the 19th century it was converted into a prison. Prior to its destruction in the 1908 earthquake it comprised a square dungeon with ramparts and reinforced by polygonal towers. Only an octagonal tower remains standing and is incorporated into the 20th century Shrine of Christ the King church, a visible Messina landmark which dominates its skyline. The name Matagrifone signifies "Greek killers" or "kill-Greeks" due to the population of Messina having been predominantly of Greek ancestry. History Medieval Matagrifone was initially constructed as a wooden fortress in 1061 by the Norman adventurer Robert Guiscard, Lord of Sicily. It was upgraded in 1190 by Richard I, king of England during his sojourn in Messina as part of his journey to the Holy Land in the Third Crusade. He ordered its partial demolition before he departed in 1191 for the conquest of Cyprus. In 1240 King Frederick II, Holy Roman Emperor ordered the rebuilding of the castle in limestone. Documents of the period refer to a Castrum novum. It later passed to the Angevin dynasty. In the aftermath of the Sicilian Vespers, the royal vicar Herbert of Orleans together with his family and the supporters of King Charles I of Naples took refuge in the castle which was besieged and damaged by the angry Messinese mob led by Alaimo da Lentini. However they were given safe conduct to leave the castle which was subsequently repaired. After the Angevins were driven out of Sicily, Matagrifone came under control of the new ruling dynasty, the House of Aragon. It became the residence of Queen Constance, consort of Peter III at the end of the 13th century. In February 1285, Baroness Macalda di Scaletta, wife of Alaimo da Lentini, and her children were imprisoned in Matagrifone Castle by the orders of King Peter. It was there she became acquainted with another prisoner, the Tunisian emir Margam Ibn Sebir of Djerba, with whom she passed the time playing chess. According to historian Santi Correnti she was the first Sicilian woman to play the game. In the late 15th century the castle was enlarged by King Ferdinand II of