Paris has about 600 impasses, cités, villas and squares: streets that come to a dead end. Cul-de-sacs, as they used to be called in French and are still called in English. Within the Périphérique, Paris is the most densely populated city in Europe, with more than 20,000 inhabitants per square kilometre. This book depicts about 200 cul-de-sacs from the 1st to the 20th arrondissement for the first time. The photographs offer a glimpse of part of Paris that usually goes unnoticed.