Kansas
Kansas was a state of the United States of America. Dodge City was one of its cities, and the home to one of its marshals in the late 1800s, Virgil Earp. (TV: The Gunfighters) The Fifth Doctor and Nyssa landed there in the 22nd century. In a corn field that was growing unnaturally large, they found a dead sheriff whose warrant card confirmed that he was from Kansas. (AUDIO: The Mutant Phase)
A phrase from The Wizard of Oz — "I have a feeling we're not in Kansas anymore" — was quoted many times by the Doctor's companions and friends. (PROSE: Matrix, Vanderdeken's Children, Relative Dementias, Falls the Shadow, Return of the Living Dad, The Face of the Enemy, Autumn Mist, The Mother Road)