Assos has always had a small population . Its location meant that under siege its supplies , including water , could be cut off . Still , the castle became the capital of northern Cephalonia as a large fort with a small settlement inside . In 1684 , the Venetians took Lefkas from the Turks and the Assos castle lost its strategic importance . In 1757 , with piracy and the Turkish threat reduced , the Venetians founded Argostoli , which became the main town of the island . Asos remained the seat of the Venetian '' provveditore '' until the Fall of the Republic of Venice and the end of Venetian rule in Cephalonia . In 1822 , about 1700 people came from Souli to stay in the Assos fortress and the whole area became a quarantine area , resulting in a settlement within the fortress named Souli . For the next century , Assos continued to be a fortress without a military role . In the late 1920s , a prison was started there which after the World War II hosted political prisoners , who kept vineyards and crops of cereal . The Ionian Islands were badly damaged by the Ionian Earthquake in 1953 . After that , most people of the castle left and the prison was closed . The 1961 census found only 6 people living in the fortress , the last of whom left in 1963 . They had been known as the " Kastrinoi " ( " people of the castle " ) , comprising large families who mainly cultivated olives and grapes
Ionian Earthquake in 1953
1953 Ionian earthquake
Assos Castle