[2] Los Angeles's Water and Power Associates cite the building as featuring Spanish Colonial and Renaissance Revival/Beaux Arts architecture on different pages of the same document.

[5] In October 1935, Betty Grable hosted a costume party to celebrate Jackie Coogan's 21st birthday in the hotel, with Lucille Ball, Johnny Mercer, and one of the Dionne quintuplets in attendance.

[6] On Halloween 1936, in what would become a media sensation, Bess Houdini held her tenth and final séance to contact her dead husband on the hotel's roof.

[1] On December 1, 1954, a camera crew from the NBC show This Is Your Life surprised retired comedy legends Stan Laurel and Oliver Hardy in room 205, something the duo did not appreciate.

Other notable Knickerbocker guests during the building's heyday include Frank Sinatra, Lana Turner, Mae West, Cecil B. DeMille, Red Skelton, Bette Davis, Cary Grant, Maureen O'Sullivan, Elinor Mordaunt, Louis B. Mayer, Howard Hughes, and more.

In 1998, the Knickerbocker's neon sign was illuminated after being dark for decades, part of an effort to restore Hollywood's old brilliance and verve.