1. Les Puces de Paris Saint-Ouen — Saint-Ouen · Porte de Clignancourt
The huge Saint-Ouen group of antique markets, open every weekend of the year.
The official site, which says the Puces have operated since 1870, lists the market as open every weekend of the year, including public holidays: Friday from 10 am to 1 pm (for professionals), Saturday and Sunday from 10 am to 6 pm and Monday from 11 am to 5 pm. It lists Métro lines 13 (Garibaldi), 4 (Porte de Clignancourt) and 14 (Saint-Ouen), bus 85 and tram T3b.
Its sub-markets include Paul Bert Serpette, Biron, Vernaison, Dauphine and Jules Vallès, among others listed on the site. Hours can differ by individual stall.
Good to know: Pick two or three markets rather than trying to see everything in one visit.
Rue des Rosiers, 93400 Saint-Ouen-sur-Seine, France