A reader named Philippa has informed me that the arrondissement system that divides the city is a fairly new element of city geography:
The organization of Paris into its 20 arrondissements, spiralling out from the Ile de la Cité, seems so well established that you may be surprised to learn that the arrangement is only 150 years old. Today’s arrondissements date from exactly January 1, 1860. On that day, the city was restructured and 11 surrounding villages or communes were annexed: Auteuil, Passy, Les Batignolles, Montmartre, La Chapelle, La Villette, Belleville, Charonne, Bercy, Vaugirard, and Grenelle, along with some bits and pieces of territory that fell within the Enceinte de Thiers. Today, some of these areas retain faint traces of their bucolic past –a few winding roads, some country houses now hemmed in by urban development, glimpses of trees that were once part of orchards and are now marooned in courtyards. But in 1860, they instantly became “urban” and had to leave behind their rural roots. If you want to understand more about this watershed in Paris’s history, go to an exhibit called “1860: Agrandir Paris: 150 ans des vingt arrondissements parisiens” at the Galerie des Bibliothèques, 22 rue Malher, 4th arrondissement (2 September to 24 October, 2010), which commemorates the reorganization and annexation of 1860.
>Click here to read more about how the city used to be divided by church parishes–and how one arrondissement was almost named Brutus.