I am greatly intimidated by the 11th at St. Andrews. Knowing the history of the hole and also knowing tthat death awaits in the form of both the Hill and Strath bunkers, having to deal with the wind, and seeing the other groups of golfers playing the 7th, teeing off on 12, etc., just makes it an intense hole for me.
The 10th at Prairie Dunes is also intimidating. It plays 185yds from the back and the wind is ever present. The hole is slightly uphill, blind in parts and trouble lurking right and left, long and short. The hole rarely plays its distance - sometimes you need to take 2 or 3 more clubs and sometimes you have a helping wind of 20 or 30 mph and you have to guage how much to take off and yet still reach and hold the green. Add to that the fact that you are teeing off in front of the patio, dining room and bar and it is an intimidating hole.