The Merchandise Mart (or the Merch Mart, or the Mart), is a commercial building located in the Near North Side, Chicago, Illinois, United States. Opened in 1930, it was the largest building in the world with 4,000,000 square feet (372,000 m2) of floor space. Previously owned by the Marshall Field family, the Mart centralized Chicago's wholesale goods business by consolidating architectural and interior design vendors and trades under a single roof. It has since become home to several other enterprises, including the Shops at the Mart, the Chicago campus of the Illinois Institute of Art, and the offices of the Chicago Sun-Times.
Massive in its construction, and serving as a monument to early 20th century merchandising and architecture, the art deco landmark anchors the daytime skyline at the junction of the Chicago River branches. With upper levels bathed in colored floodlight, the structure stands out against darker downtown buildings in night views. The building continues to be a leading retailing and wholesale destination, hosting 20,000 visitors and tenants per day. The Merchandise Mart is so large that it had its own ZIP code (60654) until 2008, when the code began to be shared with part of the surrounding area. In 2010, the building opened up its Design Center showrooms to the public for the first time.