Where was Charlie, the Lonesome Cougar filmed?
1967 film by Winston Hibler, Rex Allen
Charlie, the Lonesome Cougar (1967) was filmed in Cascade Range, Enumclaw and Clearwater River, 3 places named in its Wikipedia article, in the United States. 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 3 places. Each links to the sentence that says so.

