The Wall of the Ferme générale was one of the several city walls of Paris built between the early Middle Ages and the mid 19th century. Built between 1784 and 1791, the 24 km wall crossed the districts of the Place de l'Étoile, Batignolles, Pigalle, Belleville, Nation, the Place d'Italie, Denfert-Rochereau, Montparnasse and the Trocadéro, roughly following the route now traced by line 2 and line 6 of the Paris Métro. The wall was demolished in the early 1860s, although elements of some of its gates remain.
Claude Nicolas Ledoux's Rotonde de la Villette at Place de Stalingrad
One of the two customs houses at the barrière d'Enfer, now Place Denfert-Rochereau
Rotunda in the parc Monceau, Barrière de Chartres
Barrière du Trône near the Place de la Nation