Tokyo's oldest market is not in Tsukiji or Ueno but on a narrow street in residential Setagaya, and it happens on four fixed days a year: December 15 and 16, then again January 15 and 16, whatever the day of the week. The Boroichi began in 1578, when the warlord Hojo Ujimasa licensed a free market here — a full generation before Edo itself took shape. It has run for some 440 years since, and is now designated an intangible folk cultural property of Tokyo, which means the crowd itself is, in effect, a cultural asset.

The name means "rag market": farmers once brought old cloth and clothing to trade, rags for mending kimono or weaving into sandal straps. Today roughly seven hundred stalls press along Boroichi-dori near the old magistrate's residence — antiques, old kimono, secondhand books, potted plants, New Year goods — and some 200,000 people file through on a good day. The famous purchase is daikan-mochi, fresh-pounded rice cakes sold from a single stand whose queue is a spectacle in its own right.

Ride the two-car Setagaya Line tram to Kamimachi or Setagaya station; the market begins almost at the platform's edge, from nine in the morning to eight at night. Whether you find treasure is honestly a matter of luck. But that was never quite the point. The point is to join a crowd that has been gathering in the same place since the Sengoku era — and to come back in January, if December leaves you wanting.