Of the courses I have played, it isn't even close: The par 4 10th at Yale is far and away the most difficult. First of all, teeing off over a road always messes with my head. Then, the landing area is blind, and a shot to the right might very well kick farther right into the trees. The approach is about as uphill as it gets, and the green is fronted by incredibly deep bunkers. Just getting to the putting surface is a challenge, but once there, all the humps and bumps make a two-putt less than routine. For a hole that isn't even 400 yards (I don't think), it is a beast.