Sinop Fortress Prison is the city's dark, essential sight. The prison occupied part of the old fortress from the late Ottoman period until 1997, and its location between thick walls and the Black Sea helped give it a reputation for being almost impossible to escape.
It is best known in Turkey through the writers, poets, and political prisoners held here, including Sabahattin Ali and Nazım Hikmet. The cells and walls are blunt rather than theatrical, which makes the place more powerful.