However, the Marais area near the Great Apartment, and more specifically the rue des Francs Bourgeois, has always been open on a Sunday, attracting a sizeable crowd. Now that the area is also pedestrianised on Sundays, the crowds are a little less hard to brave, but they remain crowds nontheless.
Rue des Francs Bourgeois used to look like this. Thank goodness they stopped the cars!
photo by Alan Bell used under cc licence
And rue des Rosiers in the heart of the Jewish area gets very packed, very quickly too:
photo by rsepulveda used under cc licence
Both these streets, indeed the whole Marais area, remain an agreeable, fume-free walk on a Sunday, and handy if you have a shopping urge that you just can't resist.
Checking out exactly which streets are cut off to traffic, I came across a second area near us that is also pedestrianised on Sundays: the Sentier, a little to the north. If you add to that the whole Les Halles area and the adjoining Montorgueil area, both permanently pedestrianised, it struck me that there are loads of streets to explore around us that are traffic-free much of the time!
I'll write more about each sometime soon, bit in the meantime I've made a Google map of the pedestrianised areas that you can peruse comfortably here or uncomfortably below. I'd definitely recommend heading down the rue des Francs Bourgeois on a Sunday as an interesting way to spend an afternoon, equally good in summer or winter. Try it out!