Shinsegae's flagship store is in Harold Square.
Busan ( [ pu.san ] ) , formerly known as Pusan and now officially is South Korea 's second most-populous city after Seoul . Centum City is a major multi-project urban development part of Haeundae-gu , Busan , South Korea . Shinsegae . Its flagship store in Centum City , Busan , is the world 's largest department store , surpassing Macy 's flagship Herald Square in New York City in 2009 .