Dominating the city from the north-eastern corner of its acropolis is the Heptapyrgion. Though it actually has ten towers, its name means Seven Towers and possibly refers to the homonymous fort in Constantinople, perhaps a statement that it too was equally impregnable. Various sections are dated from the early Byzantine to the Ottoman period. The fortress was converted into a prison in the 1890s and became widely known as the Yedi Kule. Common criminals, addicts, and political prisoners of both sexes were imprisoned there throughout the dictatorship of Metaxas which began in 1936, the Nazi occupation, the Greek civil war and the period of the Junta. Conditions inside the prison that was closed in 1989 were terrible, even cruel, and it is said that the cries of tortured prisoners could be heard outside the walls. In 1921, Giorgos Iordanou, a former prisoner, noted that “the tomb of the living opened for me. The sun was setting. And my youth was about to set in the irredeemable darkness of Yedi Κule.”