What's New Links FAQ Contact

Length 20 miles
Time 6 hours
Total Climb 3350 feet
Fun Rating
Scenic Rating
Aerobic Difficulty
Technical Difficulty 

GPS Track

Suggested Parking

Park Map:
    Original (PDF)

Topographic Map

Park Website


Purchase a Map
Mount Tam (Eldridge Grade and Rock Spring Trail)

This long trail ride allows you to have (almost) a full day of fun on the northern slopes of Mount Tam. At least if you're as slow as I am, that is. It traverses mostly fire roads; there's zero singletrack and you'll be on paved roads only for brief connecting segments.

I don't have an official parking spot to which I can point for this ride. You'll have to find street parking in or around Ross. So, make sure the parking you find is legal and doesn't inconvenience anyone. Another option would be to park at Lake Lagunitas (you'll have to pay an entrance fee on the order of $8 to do that) and begin and end your ride there instead.

The ride starts out from the town of Ross, near Phoenix Lake. It quickly gets on Eldridge Grade and climbs this trail all the way to East Peak. The earlier parts of Eldridge Grade that you traverse on this ride start out like any ordinary fire road in a forest. As you get higher, you get to the rockier parts of the trail. Naturally, this makes the climb more challenging. The grade is actually very steady all the way to the top (around 7% on average). If anything, it actually slackens a little bit right before the peak (to about 5%). But, it's so rocky and technical near the top that the climb will definitely make itself felt.

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 the peak and providing views like an observation deck all along the way.

Once you're ready to leave the peak, you set out on pavement. This part involves some additional climbing (350 feet), unfortunately, which can feel quite unwelcome after climbing Eldridge Grade all the way to the peak. Even after you turn off the road onto Rock Spring Trail, you start with a short climbing stretch (only an additional 200 feet) before your climbing on this ride ends for the most part and a long and flowing descent across a beautiful landscape begins along Rock Spring Trail.

You'll get an opportunity to cut the ride a little shorter, once you reach Lake Lagunitas. You can take one of multiple trails (Lakeview Fire Road, Filter Plant Road, or Fish Grade) to connect back to the earlier parts of Eldridge Grade more directly and simply return from there. The route shown on this page continues a little further instead, by taking a paved road for a short distance (with a final bit of climbing) to Shaver Grade and taking that through Five Corners before returning to Phoenix Lake.

© Ergin Guney


blog comments powered by Disqus