Jack London State Park – Mountain Trail

We hiked the Mountain Trail towards the top of Sonoma Mountain – a seven mile hike with over 1500 ft of elevation gain. It doesn’t quite reach the top which is outside of the park boundary, but it’s nonetheless a great hike.


It has been far too long since we’ve had a chance to get out and hike.  Work and other commitments have taken up way too much of our time.  We have plans to go to Yosemite in a few weeks – let’s hope the government is back up and running by then.

While visiting friends and family in Sonoma County last weekend, we made plans to stop at Jack London State Park.  We hiked the Mountain Trail towards the top of Sonoma Mountain – a seven mile hike with over 1500 ft of elevation gain.  It doesn’t quite reach the top which is outside of the park boundary, but it’s nonetheless a great hike.

This park has always been one of my favorites in the area.  The Wolf House – one of the more interesting sites – is the ruins of a 15,000 sqft mansion that Jack London began building in 1910.  Before the Londons were able to move in, the house burnt down.

On this particular visit, we did not make it out to the Wolf House or many of the other sites in the park.  Instead, we headed up the Mountain Trail towards Park Summit.  Park Summit (as it is called on the map) is the highest point in the park.  It is on the eastern side of Sonoma Mountain – less than 100 vertical feet from the summit.  Currently, the top of the peak is not exactly accessible.  A barbed wire fence marks the boundary between the park and land now owned by the Sonoma Land Trust.  A new trail to the top is in the works and should open by the end of this year.  In the meantime, the Park Summit is worth a visit.  We could see Mt Tam, Mt Diablo, the SF Bay, Sonoma Valley, Mt St Helena and Annadel State Park.

Download file: SonomaMtn.gpx

There were a few cars ahead of us a we pulled up to the kiosk.  We paid the $10 entry fee, then turned right and parked in the upper lot.  The trailhead is clearly marked.


Immediately after leaving the parking lot, we reached a large picnic area in a grove of eucalyptus trees.  Beyond the eucalyptus grove are London’s cottage and a few other old buildings.  We followed a dirt road to the right, past all of the buildings.  Soon we were on the Lake Trail, walking alongside a vineyard and heading towards the forested eastern flank of Sonoma Mountain.


At one point we reached a junction where a second Lake Trail split off to the right.  Both trails reach the lake but we continued straight, following the vineyards border.  Our route was slightly shorter than the alternative.  Soon we were hiking through denser forest – mostly redwoods.


After less than a mile of hiking, we reached the lake.  A dam was built in 1913, creating the lake.  Today, it is in pretty bad shape but the Jack London Lake Alliance is working to make repairs.  We walked across the top of the dam.  When we reached the other side, the trail continued to the right.

Looking back across the dam.  That is indeed water on the left side.
Looking back across the dam. That is indeed water on the left side.

From the lake, we followed signs for the Mountain Trail for the rest of the hike.  The trail stayed on a dirt road almost the entire way.  This would be a great beginner mountain biking route.  We climbed 1500+ ft to Park Summit.  Most of the trail wound through shaded forest.  Towards the top, our path got steeper and redwoods gave way to oak woodlands.


At 0.6 miles from the top, we reached a junction with the Hayfields Trail.  The Mountain Trail continued to the left, the Hayfields Trail to the right, and a clear use trail ascended straight up towards Park Summit.  The use trail is shorter and steeper.  We had plenty of time, so we continued up the Mountain Trail.

Use trail up to the summit.
Use trail up to the summit.

At the top we found a small clearing in the grass alongside the boundary fence.  We sat, ate some cookies and enjoyed the view.


We hadn’t seen anyone on the trail since leaving the parking lot but shortly before heading down, a friendly woman on a horse showed up.  We talked with her briefly, then she headed down.  When she turned, I realized she was a park patrol volunteer.  It’s nice to see the volunteer presence.  Since May 2012, this park has been managed by the Jack London Park Partners (JLPP), a special project of the Valley of the Moon Natural History Association.   Due to the state’s fiscal crisis, this park was scheduled to close in June 2012.  Thanks to JLPP and many volunteers, this park has remained open to the public.


We headed down and made it back to the car in less than 2 hours.  We saw a number of people hiking up the trail as we headed down.  The picnic area near the bottom was now filled with dozens of french wine country tourists eating lunch.  Two tour buses were parked nearby.  The parking lot was packed.  We hadn’t sent out particularly early, but we really beat the rush.

More Info:  The Valley of the Moon Natural History Association has plenty of park info on their website.   Under Visitor Information, you’ll find a description of this hike and others within the park.  Visit the website: http://jacklondonpark.com/

Glen Ellen, California, United States

3 thoughts on “Jack London State Park – Mountain Trail”

  1. Always meant to do this, but not so far. Not countable, by me, but I like to plain out hike, too. Assessment of chances being caught and fined for summiting?

    1. The property at the summit is owned by the Sonoma Land Trust. They plan to open it to the public eventually, but in theory it is still off limits.

      With that said, there is a large hole in the barbed wire fence bordering the park. A clear path heads towards the communication towers near the summit. There’s a post on SummitPost.org describing the actual summit.

      I would guess chances of being caught and fined are slim to none. Clearly a lot of people head up there. 🙂

      More info: http://www.sonomalandtrust.org/news_room/press_releases/081209_Walsh_Ranch_pr.html

Any thoughts?