Bald Mountain Bike Climb - PJAMM Cycling

Bald Mountain


The only Sonoma County bike climb with 360 degree views at the top.

Explore this Climb

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2.4 mph NW with gusts up to 5.9 mph

0% chance of light rainfall

5:53 AM (local)
PJAMM Sunrise Icon5:54 AMPJAMM Sunset Icon8:22 PM

Wind Speed


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74° 51°


pjamm cycling partly-cloudy-day weather icon

65° 49°


pjamm cycling partly-cloudy-day weather icon

65° 48°


pjamm cycling partly-cloudy-day weather icon

58° 46°


pjamm cycling partly-cloudy-day weather icon

67° 48°


pjamm cycling clear-day weather icon

72° 51°


pjamm cycling clear-day weather icon

77° 52°

Climb Summary

Bike climb up bald mountain - map at the top with mountains 

Cycling Bald Mountain - very challenging - 33 mm tires recommended.

Ride 4.1 miles to 2,733’ gaining 2,122’ at 9.5% average grade.

Steepest ¼ mile is near the top - 17%

This climb ranks as the #2 most difficult on the Tri-County Top Climbs list with  an  eye  popping (for these parts) FIETS Index of  6.15 (this is only 1 of 2  climbs in the tri-  county area that top 6 on the FIETS scale). Located in the  Mayacamas Mountain  range, Bald Mountain is, for a number of reasons, a  very challenging ascent, but with  360 degree views from the top  unparalleled in Sonoma/Napa/Lake counties.  

This climb is located in Sugarloaf State Park (4,020 acres) which is in the Mayacamas Mountains. Bald Mountain is the high point of the park and we climb to the top on this bike ride.  The Bald Mountain is situated between the lush Sonoma and Napa valleys and both are visible from the climb’s finish.  Bald Mountain and Mt. St. Helena (Napa/Sonoma) are the only points in Wine Country where you have 360 degree views of Sonoma and Napa vineyards.

 From its peak at 2,673' (by our Garmin - the official elevation is 2,729')  we have  spectacular and unobstructed views of the Sonoma Valley to the west, San Pablo  Bay/Mt Tamalpais to the south, Mt. Diablo to the southeast, Napa County to the  east,  and Mt. St. Helena to the north.

Climb Bald Mountain by bike - bicycle leaning against map at top with mountains in background   


  Bicycle ride to Bald Mountain - view from top to west and sonoma valley 

View west of Sonoma Valley

  Traffic/Roadway surface:  O.k. - here's the rub.  The first mile is on a well  maintained and good state park road.

Bike climb to Bald Mountain - road and forest - start of climb

 At the 1.17 mile mark, ​we turn left ​onto gravel  for .5 miles at 5.8% (manageable, even on a road bike).  

Climb Bald Mountain by bike - sign and gravel section

The  next 1.9 miles are on  very rough, broken and rutted pavement with  much gravel and debris (very, very  hazardous on the descent) at 10.6%.

Climbing Bald Mountain by bike - gate at end of gravel section

 And, that's not the worst part - at mile 3.57 we  encounter gravel for the remainder of the climb at 11.3% average grade (the first .1 at 21%).  ​

Cycling Bald Mountain - steep gravel section near the top

Dirt and 21% - The Wall

On our attempts via road bike (3 times up on cross bike - no problem), we did make it to the top once without dismounting, but this ride  is much better  suited to the cross or road bike.  The  descent, in our opinion, is the most difficult in Sonoma County.  The positive side, other than the occasional  hiker, or nutty  cyclist, no traffic as the road is closed  to all but official vehicles.