Castell d'Aro, Platja d'Aro i S'Agaró is a municipality situated in the middle of the Costa Brava within Catalonia, Spain. It occupies the eastern end of the Vall d'Aro, a narrow plain drained by the river Ridaura and positioned between the Cadiretes mountain ranges and the southern end of the Gavarres. The municipality borders Calonge to the north, Santa Cristina d'Aro to the west, Sant Feliu to the south, and the Mediterranean coast to the east, serving as a key administrative unit in this coastal region.