the Tribunal Correctionnel between 1904 and 1914. Some sections of the Conciergerie were opened to tourist visits in 1914. The Prison continued to function until 1934, when it was definitively closed. Description The Towers and facades The four medieval towers of the north facade, along the Quai de l'Horloge between the Cour de Cassation and the Boulevard du Palais, are the most prominent exterior vestiges of the old Conciergerie. The Tour Bonbec is a circular tower with battlements and a conical slate roof located at the west end of the Conciergerie, next to the Cour de Cassation. It is the oldest of the towers, constructed in the 13th century under Louis IX. It was originally one level shorter than the other towers, but in the 19th century, under Napoleon III, it was raised to its present height and form. The name of the tower comes from "Bon Bec," a slang word for a "Good talker". It is reference to the torture chamber, which during the Reign of Terror was located in this tower; it referred to those prisoners who spoke freely under torture. The gateway on the north is flanked by two circular towers with conical roofs, but without battlements. The Caesar Tower, on the left facing the building, is named in honor of the Roman Emperors, particularly Julius Caesar who visited the island during the Gallic Wars to meet with the leaders of the Gallic tribes, and the later Emperors and Roman governors who lived on the island. The two towers were constructed in the early 14th century by Philippe IV. Later in the 14th century, the lower portions of the towers were connected to the prison of the Conciergerie, and were used as dungeons until the French Revolution. The Silver Tower on the right was used to store part of the royal treasury. After the court moved to Versailles, The upper parts of the two towers were attached to the Grand Chamber of the Parliament, and were used to store the civil and criminal registries of the Kingdom. In 1793–94, at the height of the Terror, the chief prosecutor of the Revolutionary Tribunal, Antoine Fouquier-Tinville, had his offices in the two towers, close to the courtroom of the Tribunal. The most recent tower is the Tour de l'Horloge, or clock tower, at the corner of the Boulevard du Palais and the Quai de l'Horloge. It was completed by