"Castaway City" is a fictional city or a concept often used in literature, film, and video games. It typically refers to a city that is isolated or cut off from the outside world, usually due to some disaster or event. This could include scenarios such as being stranded on a deserted island, lost in space, or a post-apocalyptic setting where the city is isolated from other surviving settlements. The term "castaway" suggests a sense of loneliness, survival, and resourcefulness, as the inhabitants of the city must find a way to survive and make the best of their situation.