On pourra remarquer sur les photos ci dessous, que l’entrée du métro Courcelles a été modifié depuis. L’escalier est aujourd’hui dans l’autre sens.
Boulevard de Courcelles, the border between the 17th and the 8th arrondissement is located at the course of the former Farmers General Wall, which marked until 1860, the line between Paris and its associated villages. (see article)
Since the leveling of the wall, the annexation of the surrounding villages by Paris and the redistricting, the boulevard was shared in two. Even numbers became part of the 17th district, while the 8th District has the side odd numbers.
The Rotonde de Chartres of the Parc Monceau is one of four survivors of the old doors that were located along the Wall.
Along the Boulevard, there were four in all. First place Gourbaud Prosper (Villiers), one at Monceau (still there), another at the Courcelles Metro station (see photo), and a last place des Ternes (Barrière du Roule).
Indeed, Philippe Egalité, who owned the Park Monceau had requested that the wall be removed all along and replaced by a ditch, because it spoiled his view of the countryside.
It will be noted on the photos below, that the subway entrance has been modified from Courcelles. The staircase is today in the other direction.