You could attack this question from multiple angles. There are "courses" played across ice glaciers. There are "courses" played cross country through wilderness and deserts. But if you want to talk more or less legitimate golf courses.....
Sevillano Links, John Daly Signature course (would you expect anything less?), in Corning, CA can be played as a par 90, all par 5s, 9443 yards. I played it. It gets goofy because the course is normally played as a regulation par 72 (still 7823 from the John Daly tees) and only gets stretched to the par 90 course for special events/tournaments, but it's still legitimately a golf course and not some extreme golfing adventure. BTW....I shot 110.
I do believe I read an article a long time ago about longer courses as well. For par 72s, the ones already stated above may be the longest. But there are other courses longer with different pars. I recall one article about a course much longer that a 4-some of long-drive champions played for exhibition. I recall another course I think in Japan that is over 8000 yards as well, but has a par-6 or 7 hole or something out of the ordinary like that.
Guess I'll have to do more research.
