This is a climb from around 200 feet of elevation to the peak of Mount Tamalpais. The ride consists entirely of fire roads. It provides a sampling of spectular views in every direction from high on the mountain. If it's a clear day, it's like the view from a plane. If it's a foggy day, you experience the unique experience of climbing through clouds to reach views of distant Bay Area ridges jutting out of a "white and fluffy ocean".

The climbing portion of the ride is on Old Railroad Grade. This is the route of the railroad that used to reach the peak of Mount Tam. The most interesting part of it is its history. You get to see a rare "trail" for which hills have been cut through, get to see the site of an old station (which you'll know by noticing a "sidewalk" on the side of the trail), visit West Point Inn, and see the Double Bowknot (a series of four hairpin curves of the old railroad). Since this used to be a railroad, it also has a very steady average grade of around 6%. So, this may be the easiest way to climb up a mountain in its entirety on a bike.

Once you reach East Peak, you might want do a quick stroll on Verna Dunshee Trail before you head back down. This is a hiking-only trail, so you'll have to leave your bike behind (which means it would be a good idea to bring a bike lock with you on this ride). It's a short loop less than a mile in length circling right around the peak and providing views like an observation deck all along the way.

The downhill part of the ride is on Eldridge Grade, possibly the rockiest fire road you can find in the Bay Area. It may make hardtrail riders wish they had full-suspension bikes. It's described as "not for beginners", and the trail used to be open only to uphill mountain bike traffic until comparatively recently. So, basically, it's a blast!

There is very little parking available at the suggested parking spot referenced by the link on this page. It's just a road-side pocket where three or four cars might fit. So, you should either plan to show up to park there really early in the morning and hope that it'll be more likely to find a spot at that hour, or be prepared to park closer to downtown Mill Valley and bike from there.