Where was The Murder Clinic filmed?
1966 film by Elio Scardamaglia
The Murder Clinic (1966) was filmed in Frascati and Villa Parisi, 2 places named in its Wikipedia article, in 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.
Places per Wikipedia's article
The Wikipedia article names 2 places. Each links to the sentence that says so.