The Deadly Desert has a well-known reputation in Emerald City, though some believe it to be an urban legend. As the story goes, if you touch the desert sand, you instantly become a sand ghost, fated to wander this wasteland for all eternity! You can read more about the Deadly Desert in L. Frank Baum's book, "The Wonderful Wizard of Oz".
The Nome Kingdom is home to the Nomes of Oz, where they mine much of the magic that fuels the Fairylands. You can read all about Dorothy Gale's great-grandmother's adventures there in the L. Frank Baum book, "Ozma of Oz."
The Wheelers are one of the rarest species in the land of Oz, and one of the only creatures who can traverse the Deadly Desert without turning into sand ghosts. You can read more about them in L. Frank Baum's book, "Ozma of Oz."