Augusta National
Pine Valley
Olympic Club
Sand Hills
Cypress Point
Shinnecock
I really love the Riv, but it doesn't have enough sizzle to be considered a #1 course. It is a spectacular design, has the best short par 4 in the world, some ingenious short holes and one of the greatest finishing holes in the world, but I think it still somehow falls short. This is all personal opinion and incredibly subjective, but I think Cypress overcomes its 18th hole (which must be the worst hole on any great course) because of the majesty of the rest of the course.
I might even include LA North, but that is probably because of my great times there more than the overall merit of the course. I don't include Pebble Beach because there are far too many mundane holes