La ConciergerieThe Conciergerie [2 boulevard du Palais, +33 153406080 ad/ch €7/Free] are the conical-roofed, twin towers of the Palais de Justice (one the most prominent features in Île de la Cité). Lying on the west side of the island, the Conciergerie is the oldest part of the palace- the first royal palace to be built in Paris. Although the palace is still used for legal activities, the Conciergerie is open to the public.

Marked as a French Historic Monument, these towers were formerly used as a prison. Its most ‘active’ days were during the French Revolution and in particular, during the Reign of Terror. This was when thousands of prisoners (both male and female) were kept locked in their cells, mostly sent to the guillotines around Paris. One of its most famous inmates was Marie Antoinette, who kept here before being sent to the Salle Saint Louis to walk to the ride that brought her to the guillotine. References indicate that favoritism was high in the prison, as the wealthier inmates were able to afford beds, while the poorer ones slept on hay. After the French revolution, the towers continued to function as prison cells, but this time for high-value prisoners only (such as Napoleon III).