High fantasy is a sub-genre of fantasy fiction, defined either by its setting in an imaginary world or by the epic stature of its characters, themes and plot. Quintessential works of high fantasy, such as The Lord of the Rings, A Song of Ice and Fire, Eragon, Malazan Book of the Fallen, and The Wheel of Time, have both of these attributes. High fantasy exists on one side of a spectrum, opposite low fantasy or urban fantasy, which are set in the "real" world. Some works, such as The Chronicles of Narnia, The Chronicles of Thomas Covenant, and The Neverending Story, concern characters that travel between realistic and imaginary settings, and are thus difficult to classify on this spectrum. High fantasy is often classified as epic fantasy; however, although the two subgenres are extremely similar, the latter usually contains a wider range of main characters.