Picking up Meyer Ranch's comment from GI's roads post, I can vouch for the same road in my top 10. NB it's essential to take the N-130 that goes through Lizartza, a truck-stop village on the old national road. Things to watch out for: post siesta drunks on the wrong side of the road; especially blind corners. It's safest to ride from 12:00 - 15:00 when the natives are tanking up. Also eat lots of carrots as it's impossible to adjust your eyes when wearing sunglasses to combat the blinding sun but then enter a pitch black tunnel at full tilt. Also watch for loose masonary / rocks that litter the road after storms.
I went to Pamplona in 2000 with 3 biking friends from Amsterdam, and my wife to be. A Guzzi, a Laverda SFC, and the then brand new Ducati MHe. The dead-weight of the Guzzi got me trounced on the mountain section. My testicles are not large enough to run with bulls (or my survival instinct logic is adequately developed enough to realize better).
What's the name of the intoxicating crushed ice drink consumed locally by the jug full? Possibly related to Hemingway's Death In The Morning? More of the same please. BP