This is good debate, what are the hardest courses in Scotland? From research Western Gailles seems up there
Depends entirely on the weather and seasonal conditions for growing rough. For example, Castle isn't the hardest course in calm conditions in a dry season. However, if there has been a rainy season and the rough is dense and you get it on a windy day it's harder than a wedding dick.
Last year when we went, the New Course was by far the easiest we played and I think everyone in our group posted the 1st or 2nd lowest round of the trip there. In contrast, this year I had 4 scratch or better golfers out there and it was the firmest course we played and none of us scored well in spite of the course playing crazy short.
On a calm day with moderate dry rough, my personal rankings of
toughest to easiest of the ones I've played:
Muirfield
Carnoustie
Western Gailes
Jubilee Course
Gleneagles Centenary
Turnberry
Castle
Kingsbarns
N. Berwick
Gullane #1
Old Course
New Course
Crail - Craighead
Crail - Balcomie
Eden
I really need to get up to the northern part of Scotland and play some of the other courses listed by timdunk. I've heard the golf up north tends to be harder.
The Old Course isn't a hard golf course in the sense that you can get it around without embarrassing yourself and losing balls, hitting into water, etc. To me it feels like an "easy par, hard birdie" course in calm conditions. It's not all that hard to hit 16+ greens out there, but even really good golfers will end up with some 100 foot putts out there. One of my favorite approaches out there is #5 - The green is 80+ yards deep. It always cracks me up to hear a caddie say you have 175 to the front, 250 to the pin, and we want to fly it no more than 200 yards.
DCDeac nailed it that positioning means everything out there. Landing on the incorrect side of a VW size mound on the approach can cause a variance of 40 yards in your result. Off the tee the safe play is always left, but that almost always gives the least favorable angle of approach. The course plays really short, and every time I've walked off 18 I felt like I should have shot 5 or 6 shots lower just based on how many chances I had to make a score on a hole...but it always adds up to 73 or 74.