The Railway Exchange building stands on the northwest corner of Olive Street and Sixth Street in Saint Louis. When it opened in 1913, it was the largest commercial building in the world, with Famous and Barr Company occupying the lower floors and offices taking the upper floors. It later served as the headquarters of May Department Stores until its acquisition by Federated Department Stores. The store closed in 2013, and the building closed in 2014. See a detailed history here.