what are some of its uses?
The size of the Main Concourse has made it an ideal advertising space - during World War II, a large mural with images of the United States military hung in the concourse.
Grand Central Terminal
The size of the Main Concourse has made it an ideal advertising space. During World War II, a large mural with images of the United States military hung in the concourse, and from the 1950s to 1989, the Kodak Colorama exhibit was a prominent fixture. 
who built grand central station in new york city New York Central Railroad where is it located? At 42nd Street and Park Avenue in Midtown Manhattan, New York City.
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Grand Central Terminal [SEP] Uses
The size of the Main Concourse has made it an ideal advertising space. During World War II, a large mural with images of the United States military hung in the concourse, and from the 1950s to 1989, the Kodak Colorama exhibit was a prominent fixture. A illuminated clock hung in the Main Concourse at the entrance to the main waiting room from the 1960s to the 1990s. The clock, sometimes referred to as "Big Ben", had chimes, and after 1986, news and stock information. The clock was sponsored by at least five companies; its first and most significant was Westclox.