The Île de la Cité is one of two remaining natural river islands in the Seine within the city of Paris. It is the centre of Paris and the location where the medieval city was refounded.
The western end of the islet has held a palace since Merovingian times, and its eastern end since the same period has been consecrated to religion, especially after the 10th-century construction of a cathedral preceding today's Notre-Dame. The land between the two was, until the 1850s, largely residential and commercial, but has since been filled by the city's Prefecture de Police, Palais de Justice, Hôtel-Dieu hospital, and Tribunal de commerce. Only the westernmost and northeastern extremities of the island remain residential today, and the latter preserves some vestiges of its 16th-century canon's houses. As of 2013, the island's population was 981. The Mémorial des Martyrs de la Déportation, a memorial to the 200,000 people deported from Vichy France to the Nazi concentration camps during the Second World War, is located at the upriver end of the island.