A castle in the air is a daydream or fantasy.
Castle in the Air may refer to:
Castle in the Air (play), a 1949 play by Alan Melville Castle in the Air (film), a 1952 British comedy film based on the play Castle in the Air (novel), a 1990 young adult fantasy novel by Diana Wynne Jones The Castle in the Air, a setting in the children's book The Phantom Tollbooth A Castle in the Air [], a 1894 poem by May Kendall.
See also Castles in the Air (disambiguation) Castle in the sky (disambiguation)