Hetch Hetchy Dam Climb Bike Climb - PJAMM Cycling

Hetch Hetchy Dam Climb


All the cycling data and info you'll need to climb Hetch Hetchy Dam Climb

Explore this Climb

PJAMM Cycling LogoDark Sky logo



If you love climbing by bike and would like more detailed information on the world’s top bike climbs, join our PJAMM Cycling group and receive our Special Edition Climb Report.
  • Receive a monthly report.
  • Get detailed and entertaining information on the greatest bike climbs and climbing areas throughout the world.
  • Discover beautiful landscapes with drone video and professional photos of remote and exotic places.
  • Gain insider knowledge on where to stay and how to conquer some of the most difficult climbs.

Climb Summary

Cycling Hetch Hetchy, Yosemite National Park

Ride 6 miles gaining 1,332’ to elevation 5,126’ at 4.1% average grade.

Hetch Hetchy Road on the way to the reservoir.

Visit our Yosemite National Park page for more rides in Yosemite.

This is a fairly mild climb in Northwestern Yosemite National Park.  The climb begins at the O'Shaughnessy Dam and ends a few miles north of the park’s only entrance that does not access Yosemite Valley -- the road dead ends at the dam.   The steepest mile is just under 5% average grade so this road bike climb is more for the beauty of the Hetch Hetchy area than it’s difficulty.

View of John on the dam with Hetch Hetchy Reservoir in the background.

O'Shaughnessy Dam was constructed in 1934.

The climb begins at Hetch Hetchy Reservoir

We climb from the dam south, away and up from the dam.

Rustic scenes on the way to the climb.

This is the northernmost entrance to the park.

This is a dead end -- you cannot access the full park on this road.

It’s about 7½ miles to the dam from the Ranger Kiosk.

No fee to enter as of October 2019.

Just past the ranger station.

Start at (not on) the dam.

Just past the start of the climb -- riding up the road from the reservoir.

View from the road about a mile up from the dam.

View about halfway up the climb.


Hetch Hetchy Valley was revered as a scenic equivalent to Yosemite Valley before the dam was built.

Photo:  sfchronicle.com

San Francisco began efforts to dam the Tuolumne River at the western end of the Hetch Hetchy Valley in the early 19th Century.  Of course, the project was opposed by environmentalists and naturalists who respected and appreciated the delicate beauty of this unique and spectacular area.


June 25, 1913 SF Chronicle article.

Notice the article references John Muir, calling him “chief of the nature lovers.”

Photo:  sfchronicle.com 

The 1906 earthquake and fire exposed San Francisco’s inadequate water supply and led to efforts to tap the Tuolumne River as the primary water source for that city.  This led to a seven-year environmental battle with John Muir and the Sierra Club.  In 1913 Congress passed the Raker Act which permitted a dam to be constructed in Yosemite National Park’s Hetch Hetchy Valley.  Construction of the dam began in 1914 and was completed 20 years later in 1934.  Hetch Hetchy Reservoir provides water for 80% of the City and County of San Francisco.  

Moccasin is a company town owned almost entirely by the City and County of San Francisco.

Moccasin is occupied by employees who work for the Hetch Hetchy Water & Power System.

Yosemite National Park

Photo, from upper left clockwise:

El Capitan; Western Entrance; Tioga Pass; Hetch Hetchy Dam; Glacier Point (middle).

That’s a wrap!