This is my Marin Fire Road Training Loop, which covers over 27 Miles and contains about 5k feet of climbing. This is a two or three bottle ride.
Many long climbs with steep grades. No singletrack here, all fire roads!
Start at Shafter Bridge parking lot along Sir Francis Drake Rd. (limit one hour) across from the campgrounds and salmon hatchery. Ride up Shafter Grade Trail Kent Dam to Bolinas Ridge
. At the termination of Bolinas Ridge
turn hard left and ride down to the far side of the Alpine Dam along Kent Pump spillway. Duck under the gate and ride down Kent Pump Road
along Lagunitas Creek. After a few miles turn hard right uphill up the lonely Old Vee Road
and then continue left onto the Oat Hill Fire Road
for a combined long climb. You might feel lonely and/or lost on this ride if you have never done it before.
At the top of Oat Hill Fire Road
turn hard left onto Pine Mountain Fire Road
and climb. You'll come to a 3-way intersection at a large rocky clearing and stay left on Pine Mountain Fire Road
(if tired go straight down San Geronimo Ridge Road
. The ride starts to get pretty tough here. Pine Mountain Fire Road
is rolling, steep, and never flat. You get excellent views of Mt Tam from here along the ridge. Pine Mountain will meander up, then down, and a bit North, and then along the edge of Kent Lake with a few small creek crossings. You'll not likely see anyone else around here. Climb climb climb up and out to a 4-way intersection with San Geronimo. Stay hard left onto San Geronimo Fire Road at this intersection and climb some more (study the maps and you'll see a possible cut-through along Hunt Camp Fire Road.
Ride San Geronimo up, rolling, and then down through the trees back to Lower Peters Dam Road and to the parking lot where it all began.
A more detailed account of the history of the region can be foune here