The Conciergerie is at the heart of the city, and the heart of French history. It is a part of what remains of the medieval Palais de la Cité, located next to the Sainte-Chapelle. It was the first French royal residence. It became a prison and the "antechamber to the guillotine" during the French Revolution.

The first stones of the Palais de la Cité go back to the year 306, where they were part of the defensive wall that surrounded the island. As a major strategic asset, it needed to be protected. The first Frankish kings moved into this part, called the "pallatium".

In the 14th century, part of the Palais was converted into a prison. This is now the Conciergerie. Visitors can see the guard room, the kitchens, the long hallway known as "La rue de Paris", and the room where convicts where prepared to go to the guillotine. There are sumptuous Gothic rooms and glacial prison cells, including that of Marie-Antoinette. During the French Revolution, the judicial administration took possession of the Palais, and put the current courthouse building there, whose entrance is today located on the Quai des Orfèvres.