A prison fit for a count © Boris Stroujko/Shutterstock
Château d"If, off the coast of Marseille, France, was built beginning in 1524 as a fortress by King Francis I. The tiny islet in the Mediterranean Sea was chosen as the site for the fortress because of its steep cliffs and strategic location near the busy port of Marseille. While the "château" never gained fame defending the ancient port (since it was never attacked), it did become notorious as a prison. Surrounded by treacherous currents—like Alcatraz in San Francisco—starting in the late 16th century it was a dumping ground for political and religious prisoners. As far as official records go, none of the prisoners condemned there ever escaped.