Where was The Secret of Dr. Orloff filmed?

1964 film by Jesús Franco

The Secret of Dr. Orloff (1964) was filmed in Alcalá de Henares, Aranjuez, Royal Monastery of San Lorenzo de El Escorial, Guadarrama, San Martín de Valdeiglesias and Barajas, 6 places named in its Wikipedia article's Production section, in Spain. Wikidata records no filming location for it at all, so the article is the only recorded source. Each place says where its claim comes from.

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