Mosquito Ridge Bike Climb - PJAMM Cycling

Mosquito Ridge


Isolated climb in the Tahoe National Forest of the northern Sierra Nevada Mountain Range.

Page Contributor(s): Dan Razum, Campbell, CA, USA; Dan Magaw, Auburn, CA, USA.

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Climb Summary

Cycling Mosquito Ridge: a very remote northern Sierra Nevada bike climb.

Ride 18.2 miles gaining 5,266’ to elevation 5,989’ at 4.9% average grade.


Climb begins just over this incredible bridge.

Mosquito Ridge Road is a comfortable and fun ride into the remote regions of Tahoe National Forest starting about 25 miles east of Auburn, California (off Interstate 80).  The climb can be completed in many ways (see spreadsheet below).  The climb is never too steep and offers great views of distant heavily forested mountains and deep ravines (which we ride along), until about mile 10.5 when we leave the ridgeline and enter a gradual final 7.5 miles surrounded by pine and fir trees.  


View back down at the bridge and start from three miles up the climb.


We encountered no traffic other than a couple logging trucks.

Fittingly, we end the climb on a Forest Road.

The roadway is two-lane divided by a center stripe for 95% of the climb and is in very good condition as of October 2015.  There is very little traffic and this is a very safe and comfortable ride, although there are some sheer drop-offs on the downside of the steep mountainside as we ascend, but nothing that causes a safety concern for cyclists.

A great place to start any Mosquito Ridge Climb sequence is Foresthill.  One can stay overnight at the Forest House Lodge,  or, as Charles Samson notes below, you can park in the post office parking lot and begin from there.  Great coffee and adequate burgers are available at Stone’s Brew in town.  There is also a full service grocery store -- Worton’s Market -- about a mile down the road prior to the start of the climb that is terrific for stocking up with supplies.  Worton’s also has a very nice Deli.


We really enjoyed this climb and its surroundings and highly recommend it.  Further description for the climb follows:

Steepest ¼ mile and mile begin at mile 6 (11.9% and 7.7% respectively).

The Website Jay's Essential Bike Rides has an excellent summary of (and encouragement for) this climb.  

PJAMM contributor Charles Samson writes of his June 1, 2014 Mosquito Ridge climb (note: this summary includes the 10 miles to and from the start of the climb):

Staging location is in Foresthill at the Post Office parking lot. From there you descend about 10 miles to the Middle Fork of the American River. My advice is to carry extra water down to the bridge and stash it for the return trip up the 10 mile climb, a must. The road surface is in great shape from Foresthill all the way to top of Mosquito Ridge. From the bridge at the American River the climb starts proper, 18 miles of moderate grade winds you up and around the divides with beautiful views leaving the river behind. There is seasonal water at Big Tree Groves campground which is about 15 miles up the climb (follow the entrance road, water is next to the restrooms). Once at the top, mile 18, it's time to decide whether to carry on to French Meadows Reservoir or double back, which most riders opt for. The full loop ride is a 10 star effort, dropping down the grade the road narrows leading to and across the dam at the reservoir. Keep right at all intersections and you’re golden. The road condition is fair, but heads up as always! The road will descend abruptly once again to the river, after cooling the brakes you'll have a short stair step of a climb after which you'll reconnect with Mosquito Ridge just above the bridge. As a footnote, a great spring to refill bottles round the back side on the 22 road (forest service route) which you should be on. Look and listen for it on the right side of the road perhaps three or five miles past the damn, two bottles gets you back to the bridge and your water stash, no worries.  Here is where this ride can become epic, if it's on the warm side you'll have done well to have stashed water, it can be a cooker for some and all, been there when it was hot more than once. Ride smart, save it for the finish on this ride, either route you choose, you'll be happy you did. This is one of my favorite rides out there, just a classic euro style climb, long and steady.  

Here is Charles’ Strava route for this out-and-back climb.

PJAMM contributor Estace Yambot helps out with a very nice history of the area and summary of the climb:  

Hell Hole Basin: Over a million years ago, Hell Hole Basin was under an ancient ocean.  Volcanic Mountains formed then the Glaciation Period began, a large sheet of ice formed at the highest elevation.  Over the next million years, the glacier advanced and receded, carving the broad U-shaped valley of the Hell Hole Basin.  Hell Hole is an artificial, crescent-shaped lake in the Sierra Nevada mountain.  

Today this canyon is a camping, fishing and hiking and cycling destination.  Situated at Tahoe National Forest and located around 40 miles away northeast of Foresthill, the ride begins from the small town of Foresthill then immediately a 10 mile 8% descent to Mosquito Ridge.  The view is majestic and spectacular, meandering through granite canyons and the verdant forest.  It offers tree lined backroads and breathtaking vistas of the pristine American River, the grandiose of the sweeping plateaus and the winding mountain roads.  From the drop down, you get greeted right away by an 18-mile climb totaling 4500 feet gain towards the east side of Mosquito Ridge, with an average gradient of  4-18%.  The steady and hard ascent offers the sublime view of the American River from the canyon view, making the squiggly river smaller and smaller as the climb progresses.  At mile 18 you find some respite on some false flats as opposed to a constant climb.  Finally you get a glimpse of the French Meadow Reservoir and take a little comfort in the descent, still enjoying the beautiful wilderness into deep and breathtaking canyons towards Hell Hole Basin.  This ride will definitely question one's resolve and fitness.  It offers wild adventure and definitely an enjoyable ride giving you the opportunity to find a bit of your inner solitude.

Note:  The Strava segment we include on our page covers the first 15.1 miles of our route, ending three miles and 460' down the hill.