Where was The Strange Vice of Mrs. Wardh filmed?

1971 film by Sergio Martino

The Strange Vice of Mrs. Wardh (1971) was filmed in Vienna, Schönbrunn Palace, Sitges, Semmering and Papanice House, 5 places named in its Wikipedia article, in Austria, Spain, Italy. 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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