MTB Project Logo

blueBlack Fairfax-Bo Ridge Gravel Grinder

  4.3 ( 10 ) Favorite


43.3 mile 69.6 kilometer loop
10% Singletrack


Ascent: 3,638' 1,109 m
Descent: -3,638' -1,109 m
High: 1,664' 507 m
Low: 70' 21 m


Avg Grade: 3% (2°)
Max Grade: 28% (16°)


Driving directions Take a virtual tour
Zoom in to see details
Map Key

Trail shared by S. Lengyel

Maximum dirt, minimum traffic, amazing views along this big, mostly fire road, loop.

S. Lengyel

E-Bikes Unknown

Features -none-


Gravel grinders on MTB Project? Sure!

This is a 40+ mile mostly dirt loop from Fairfax. It is the type of loop we would want to ride if we were visiting Fairfax on a bike trip. Maximum dirt, minimum traffic, epic views, tough climbs, shady forests, etc. This ride has it all.

This ride is mostly fire road and ranch road doubletrack, linked together by lightly traveled pavement sections. It flows best as a clockwise loop, but can be ridden in either direction. Clockwise does most climbing on pavement, most descending on dirt.

You can do this ride on any knobby tire bike (and I have done it on my full suspension bike), but it is best suited to modern gravel/adventure bikes. At 40+ miles, it would be a long day on a big travel bike, but totally doable. Recommended bikes for this would be gravel bike with 35mm-40mm tires (your most fun), cyclocross bike, or hardtail mountain bike. You can have an epic day on a full suspension bike, of course, it's just going to be slower on the road sections.

This ride is designed for those wanting maximum views AND good mileage.

This ride is not very technically challenging but does have lots of short steep climbs, rutted rooty descents, and lots of miles. Technical rating is moderate. The ride is tough because of distance.

Need to Know

As always, be prepared with plenty of food, water, tube, pump, multi-tool. There is a 20+ mile section with no services on this ride.

There is water at the Meadow Club, in Samuel P. Taylor campground, and stores in Lagunitas and Woodacre.

Keep cattle gates closed on Bolinas Ridge! Expect cows and dodging cow pies on the lower half of Bolinas Ridge.


This ride starts in Fairfax and climbs through the Marin Municipal Water District watershed around the Meadow Club golf course. You'll climb on the pavement of Fairfax-Bolinas road for approximately one mile before hitting the dirt again on Pine Mountain Fire Road.

Grunt through a steep, exposed, rocky climb before turning onto Oat Hill Fire Road/ Old Vee Road for a rolling (mostly descending) ride to Kent Pump Road.

Enjoy the shade of Kent Pump Road as you make your way to Alpine Dam for a shady 2.4-mile pavement climb to Bolinas Ridge. Bolinas Ridge is an 11-mile section of rolling dirt with shady forests and open grass on old ranch doubletrack. Bolinas Ridge features gorgeous views, shady redwood groves, ferns, flowers, wide open grasslands, cows, and some short steep climbs.

You'll hit the pavement again on Sir Francis Drake Blvd for a 1/2 mile before turning onto the Cross Marin bike path where you'll have no vehicle traffic until you cross back over the creek at Shafter Grade Trail (Kent Dam to Bolinas Ridge).

It's a road burn on lightly traveled back roads through San Geronimo Valley to the last dirt section on Old Railroad Grade Trail back to the neighborhoods in Fairfax.

I placed the start of this ride at Sunshine Bikes in Fairfax because there is a bike shop, brewery, coffee shop and health food store within a 1/2 block. You can start this ride anywhere in Fairfax since parking in downtown Fairfax gets crowded on weekends. There are also numerous options to extend this ride into a true long-distance gravel grinder epic.

Please let me know in the comments what you think of the route!

Rate This Featured Ride

Rate Quality

   Clear Rating

Rate Difficulty

Share This Ride

Check In


Apr 14, 2019
Emily Vince
Mar 16, 2019
Colin Allen
Not convinced this entire route is suitable for rigid, drop-bar bikes. 42.4mi — 3h 45m
Feb 23, 2019
Hernan Jaramillo
Jan 2, 2019
Ryan James
Dec 8, 2018
Aaron Kint
Very amazing place for group rides 10mi
Nov 16, 2018
Paul Champommier
Nov 7, 2018
Rafa Lu
Oct 21, 2018
Mark Martindill

Trail Ratings

  4.3 from 10 votes


in Marin County


  4.3 from 10 votes
5 Star
4 Star
3 Star
2 Star
1 Star


in Marin County


in California


591 Views Last Month
18,716 Since May 13, 2016
Intermediate/Difficult Intermediate/Difficult


MTB Project is part of the REI Co-op family,
where a life outdoors is a life well lived.

Shop REI Mountain Bike

MTB Project is supported by

Support Your Local IMBA Chapter