A fourth, 21-story section was then added, bringing the number of rooms to 2,210, but was sold in 1937, becoming the Hotel Chicagoan; in the 1950s this was operated under lease by the Morrison.

[4] In the skyscraper hotel, the Terrace Casino opened in 1936 with a performance by Sophie Tucker and was an important Big Band venue; the Carousel in the Sky was the world's highest nightclub; the Jockey Club on the first floor was the site of protests by the National Association for the Advancement of Colored People that forced removal of its black jockey statues.

Presidents Truman, Eisenhower, and Kennedy and Vice-presidents Barkley and Nixon stayed at the hotel;[2] boxer Jack Dempsey was also a frequent guest.

[2][4] Joe "Hold 'Em" Powers spent a world record 16 days on the hotel flagpole in 1927, despite losing six teeth when wind blew him into cables.

[5] In June 1937, the hotel served as the location in which the Chicago Herald-Examiner kept the notorious murderer Robert Irwin sequestered while negotiating terms of his surrender to authorities in Manhattan.