The Santa Margherita Ligure fortress is located at the foot of a hill on which the Villa Durazzo-Centurione now stands. It was built following a resolution by the Senate of the Republic of Genoa in 1550, and it was meant to defend against raids from the Barbary pirates. It was designed by Antonio de Càrabo, who was also responsible for the construction of the Castello di Rapallo.
Construction began in 1550 and it was completed by September of the same year. Various structural interventions and armament upgrades took place until the early 17th century. After pirate attacks ceased in the 18th century, the fort lost its military importance and only some repair and maintenance works were undertaken.
In the 19th century, there were plans to demolish the building twice: first to build a new municipal building after Rapallo was established as an independent municipality, and then to enlarge the adjacent Calata Vittorio Emanuele. It was restored after World War I and it was dedicated in the memory of the fallen in that war.
References:Varberg Fortress was built in 1287-1300 by count Jacob Nielsen as protection against his Danish king, who had declared him an outlaw after the murder of King Eric V of Denmark. Jacob had close connections with king Eric II of Norway and as a result got substantial Norwegian assistance with the construction. The fortress, as well as half the county, became Norwegian in 1305.
King Eric's grand daughter, Ingeborg Håkansdotter, inherited the area from her father, King Haakon V of Norway. She and her husband, Eric, Duke of Södermanland, established a semi-independent state out of their Norwegian, Swedish and Danish counties until the death of Erik. They spent considerable time at the fortress. Their son, King Magnus IV of Sweden (Magnus VII of Norway), spent much time at the fortress as well.
The fortress was augmented during the late 16th and early 17th century on order by King Christian IV of Denmark. However, after the Treaty of Brömsebro in 1645 the fortress became Swedish. It was used as a military installation until 1830 and as a prison from the end of the 17th Century until 1931.
It is currently used as a museum and bed and breakfast as well as private accommodation. The moat of the fortress is said to be inhabited by a small lake monster. In August 2006, a couple of witnesses claimed to have seen the monster emerge from the dark water and devour a duck. The creature is described as brown, hairless and with a 40 cm long tail.