The Castle of Montalban (Castillo de Montalbán) is a castle in San Martín de Montalbán, province of Toledo, Spain, that stands 100 metres above the Torcón river[1] The castle has been owned by the Duchy of Osuna since the 15th century and was declared a historic monument in 1931.[1] The Asociación Hispania Nostra has included the castle on the 'Lista Roja del Patrimonio', a list of historic heritage at risk.[2]