Where was The Mark filmed?
1961 film by Guy Green
The Mark (1961) was filmed in Ardmore Studios, 1 place named in its Wikipedia article's Filming section, in Ireland. 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 Filming section
Wikipedia’s Filming section names 1 place. Each links to the sentence that says so.
Also shot in these places
The Blue MaxWar film1966
The Green KnightFantasy film2021