The official ruling on Marin Ave is that it is max 3.5% grade. Ha ha ha... just messing.
Well, it is insane and legit. Let me give you some geeky stats.
Along Marin, from San Pablo to Hillsdale, it is 2.09 miles (11,035.2 ft). It climbs 817 ft. 817/11035 = 7.4%.
And the REALLY steep part: Along Marin, from Arlington/Sutter to Hillsdale, it is .61 miles (3,220.8 ft). It climbs 541 ft. 541/3220.8 = 16.8%!!!!!!!!!!!!! Is that right? I gotta check another site. Bender interjection: this doesnt account for the flattening at cross streets. There are sections here that are well beyond 20%! It is all I can do to get up these hills in my 39x27!
See the attached pics for all the details. It's actually pretty cool. The site is www.bikeroutetoaster.com You can click on "Map" then click on "course point" in the upper right, then away you go. You can create an account to save the routes.
By the way, awesome news about the 2009 Tour of California this February. The last stage is a mountaintop finish on Palomar Mountain!!! Are you kidding me? That is frickin awesome! When I told Cezanne she was like "that's exactly what you said they should do!" I thought that would be so cool. Not to have the last stage be Palomar, but to finish up Palomar.
The Tour of California organizers are working with ASO, the Tour organizers, so they've expanded to 9 days to cover more of California. Palomar is the Alpe d'Huez of California, I think. It's got all the swithbacks and kind of the same length and gradient.
I actually did the pics of the ride up Palomar and the gradient, etc. Turns out to be 6.65 miles at 7.9%.
Here is the link to the article about the ToC.
I love this stuff! I can't wait to retire from the Navy then get hired on as a Soigneur for a pro team... :)
Alright, enough geeking out, time to have some icecream.