Where was Madhouse filmed?

1974 British film directed by Jim Clark

Madhouse (1974) was filmed in Twickenham Film Studios, 1 place named in its Wikipedia article's Production section, in the United Kingdom. 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.

See them on the map → Wikipedia Source data

Places per Wikipedia's Production section

Wikipedia’s Production section names 1 place. Each links to the sentence that says so.