Established 1941. Buy 10 brass coins for 5,000 won at the entrance, then walk the market trading them for tteokbokki, japchae, jeon, fried fish, whatever fits in the tray. Eat in the communal dining hall. The most fun food experience in Seoul under 10 bucks. Tongin Market introduced its now-famous yeopjeon dosirak (brass coin lunchbox) system in 2012, using replicas of Joseon-era currency.