Update [2008-4-2 14:32:18 by chris]: Pez does their rating today. Verdict? Less data, more pictures.
I love the Tour of Flanders website. What other race has a separate page for each climb on the course? Clearly the HNB folks know who the stars are. Anyway, I've never ridden the course, and the following ratings come from distilling information on the site. If you have been lucky enough to actually recon these hills, please feel free to help adjust what I've written. This is, after all, a community-edited site. Oh, and we're going to use the Wong-Baker Pain Scale to rate them.
All asphalt, 1.2km at 5%... really, this is about as easy as it gets at De Ronde. But there are stretches of 13%, so we'll call this a 1: hurts a little bit.
Short (375m), 5.9%. Even with cobbles, this can't be a problem. From its position in the race, the peloton isn't likely to be tearing it up at this stage. 0: no hurt
Under a half-kilometer, but ramps of 14% on the cobbles, which make up most of the slope. 1: hurts a little bit
645meters on asphalt... but up to 17%, and 8%v average. Plus, the profile shows some other rises and cobbles around. 2: hurts a little more
Ah, now things start heating up. This climb, included every year since 1974, comes at about the 182km (of 260) mark, and after a mellow stretch. It's business time. The climb itself is the day's longest, 2.2km, with cobbled ramps topping 11%. 2: hurts a little more
All of 360 meters... but averaging 13%, all on cobbles, maxing out over 20%. Right after the Oude Kwaremont. 3: hurts even more
Needs little introduction. One of the hardest climbs in the world of Cycling. As for numbers, 600 meters, 11.6% average, maxing at 22%. Some of the ugliest cobbles in Flanders, only recently deemed safe enough to ride. Guys will be walking. 5: hurts worst!
By itself, this could rate a zero: 700 meters at a steady 6.7%. But so close on the heels of the Koppenberg? 2: hurts a little more
Really only about 200 meters or so of serious (15%, cobbled) climbing, but bunched closely with the last two entries here, that's enough.4: hurts a whole lot!
All asphalt, and comes after a little breather. The peloton will be crackling with urgency, but with a gauntlet of hills ahead, this will be uneventful. 1: hurts a little bit
Hm, gotta wonder when the collective nerve of the pack will break. The short ramp here of 14% ain't nuthin, but it's paved, and the rest of this climb is mellow enough to produce a mere 4% grade. 2: hurts a little more
The pressure will surely be on by now. Just under 1km at a steady 7%, on pavement. 3: hurts even more
Steeper but shorter than the Berendries, with ramps up to 12.8%. But race-winning attacks have been seen here often enough, which means this hill will be climbed at a ridiculous speed. More than any other hill, the race factor changes how the hill would score on its own. 4: hurts a whole lot.
A cut below the Valkenberg: 455m at 6.4%, paved. The race will be going so fast, the leaders might barely notice it. 3: hurts even more
First time in de Ronde! 610 meters at 6% doesn't sound like much, but it starts easy and keeps getting worse (12.5%). This will be a huge strategic moment, and the racing will be immense. 4: hurts a whole lot!
Needs little introduction. 453 meters, over 9% avg and 19.8% max. There will be blood. 5: hurts worst
At this late in the game, everything freaking kills. Plus, urgency will be off the charts, and there's 3-400 meters of 11%. 4: hurts a whole lot
Sounds like fun, eh?