Fnideq is a town located in northern Morocco on the Mediterranean coast within the M'diq-Fnideq Prefecture. Situated approximately 31 kilometres north of the city of Tétouan, it is also known by its Spanish name, Castillejos.
The town serves as the closest Moroccan urban commune to the Spanish exclave of Ceuta, though the rural commune of Belyounech is geographically closer. Historically, Fnideq was the site of the decisive Battle of Castillejos during the Hispano-Moroccan War of 1859.