The only flea market I remember (it has been quite a few years since my last trip to Paris) was at the port de clingencourt metro stop. There is the 'regular' flea market with the touristy stuff, then if you walk past that there is the antique flea market with all kinds of neat booths in every corner and crevice-some booths are upstairs and downstairs-lots of art, furniture, nick-nacks (especially old smelling salt containers and antique oil lamps), rugs, vintage clothing, vintage jewelry, ribbon, etc.
I wonder is that is the marche aux puces he is talking about? I am long overdue for another trip to Paris
