The mega Macy's flagship at Manhattan's Herald Square (Broadway and 34th Street). The sign proudly proclaims it as the world's largest store. That it was between 1924 and 2009. In that year, the 2,172,000 square foot buying behemoth was bested. A 3 million square foot store was opened by Shinsegae, in Busan, South Korea.
Photo from Wikipedia / Mike Strand