The Old Chicago Main Post Office is a nine-story-tall building in downtown Chicago. The original building was designed by Graham, Anderson, Probst & White and built in 1921, but the structure was expanded greatly in 1932 in order to serve Chicago's great volume of postal business, swollen by the mail-order businesses of Montgomery Ward (the largest retailer in the United States) and of Sears (its competitor). The Old Post Office is home to many corporate offices including Walgreens, Ferrara Candy Company, PepsiCo, Cisco Systems, Uber, CBOE, Home Chef, and more.