Urban fantasy is a subgenre of fantasy defined by place; the fantastic narrative has an urban setting. Urban fantasy exists on one side of a spectrum, opposite high fantasy, which is set in an entirely fictitious world. Many urban fantasies are set in contemporary times and contain supernatural elements. However, the stories can take place in historical, modern, or futuristic periods, and the settings may include fictional elements. The prerequisite is that they must be primarily set in a city.
Urban fantasy describes a work that is set primarily in the real world and contains aspects of fantasy. These matters may involve the arrivals of alien races, the discovery of earthbound mythological creatures, coexistence between humans and paranormal beings, conflicts between humans and malicious paranormals, and subsequent changes to city management.
Although stories may be set in contemporary times, this characteristic is not necessary for the fiction to be considered urban fantasy, as works of the genre may also take place in futuristic and historical settings, real or imagined. Author Marie Brennan has set urban fantasy in Elizabethan London, while author Charles de Lint has featured the genre in the fictional city of Newford.