Hardest course: I'd say Merion. Tee to green, it's a tougher test than Bethpage. But unlike BPB, the course doesn't let it's guard down on the greens. Everything about the course is challenging and I'm finding the Michelin Challenge conditions make it absolutely brutal.
Honorable mentions: Oakmont, Olympic Club, Bethpage.
Hardest hole: So many to pick from.
Bethpage #15 I've found that the front bunker is not a bad place to miss with the pin up front. That back to front putt is the toughest 2 putt in the game for me.
Oakmont #9 That green is evil, especially with the right-front pin. Like above, I'll take the front bunker all day over a longish putt from above the hole.
St Andrews #17 Haven't even been close to a birdie here. Long left is a good miss as it leaves an uphill chip shot.
Bethpage #7 Unreachable in two most of the time for me, and to add insult to injury, the pin is tucked front-right about 90% of the time..negating any chance for a 3.
Congressional #11 Water right is a ball magnet. Aim the approach a bit left and you'll just catch the trap, leaving 30 yard bunker shot across a tiered green. 4 is a great score here.
Merion #5 Like most tee shots on this course, it just doesn't set up well to the eye. The green is diabolical. There is really no good place to miss here and the green does not reward good shots. That said, I made 3 here last time around. Yay!