10 rue des Rosiers the restaurants "les 7 lézards" (the 7 lizzards) shelters in its back yard a part of the wall that has become very ugly, but genuine. That part was formerly inside the garden of the Hotel d'Albret. Alexandre Gaudy, in his book "A la Découverte de l'Enceinte de Philippe Auguste" (discovreing Philippe Auguste's wall) tells us that half a tower would have survived at n° 8, and its outside coating would be visible at the back of the garden situated 33 rue des Francs Bourgeois, in a workshop.
This garden seems to be between 8-10 rue des Rosiers and 31 rue des Francs-Bourgeois, house of the Direction des Affaires Culturelles de la ville de Paris. A very nice civil servant working there has told us that a project to give public access to that garden was in progress. Let's meet there in 10 years ...

restaurant les 7 lézards
which no longer exists any more in 2009 !