Alvan Cordell "Hap" Hadley (March 16, 1895, Findlay, Illinois – August 4, 1976, Los Angeles, California) was an American artist specializing in pen and ink representations of popular subjects. He created posters for various films, including Buster Keaton's The General (1926) and Charlie Chaplin's The Circus (1928), as well as promotional posters for the Ringling Bros. and Barnum & Bailey Circus and billboards for Roy Rogers.