Mine is Pine Valley and its not close, at all.
I just played it for the first time a few weeks ago, and to me, it is in another class by itself above any of the other great courses i have been luck to play (CPC, Pinehurst #2, Shinnecock, etc, etc). As a scratch golfer who loves nothing more than getting beat up by a hard course, it was the ultimate test, and I have never played a course with such diversity among holes. I feel very cnofident it will remain #1 on my list for my life, and quite frankly, I am surprised that so many people who have played it don't have it at the top of their list.