Trip Summary

What: trail hiking near home
Where: San Francisco Bay Area
When: April 26 – May 2, 2022 (7 days)
Distance: 125 miles
Highlights: wildflowers, oaks, great views, well maintained trails and easy logistics

Why we went

The Diablo Mountain Range stretches from the Sacramento River delta south to Henry Coe State Park. The valleys are developed, but there has been an extensive effort over the past 90 years to protect most of the hilly areas. We are very fond of the oak savannah landscape, with its wildflower displays and extensive vistas. From November through April or May the grass is green and the hills are lush. We took this hike in order to enjoy the hills while the grass was still green, the spring wildflowers were blooming, and the temperatures were not unreasonably hot. The route was designed to make use of public transit so we left our car at home.

We had created and walked a similar route a few years ago: the Big Diablo Loop. This new hike is a bit shorter and follows a similar, but not identical route. We are always looking to walk trails new to us and were able to included a few of these in this walk. We took the ferry from San Francisco to Vallejo, which we had never done before.


The East Bay Regional Park District has downloadable maps for each of their 65 preserves.

Save Mt. Diablo, a local land preservation group, sells a very detailed map covering about half of the route. The map is so big that it is hard to handle in the field, but it is durable plastic and has excellent graphics.

The John Muir Land Trust is active in the northeast portion of this route and has maps and guides to their preserves.

Pay attention to the publication dates on maps, as the NGOs and government agencies are actively purchasing park land in this area and often open new trails.

Two annual permits are required and are easily obtained by phone, e-mail, or mail:

Click map to open an interactive CalTopo map in a new browser tab. Instructions for using CalTopo.

Amy’s Assessment

This was a fun, refreshing, and straight-forward hike with easy logistics. We were on maintained paths the whole time, so the walking was easy. This was our third consecutive year of severe drought (~50% of normal rainfall), so the wildflower display was a bit subdued, but the oak leaves were flushing out and the landscape was beautiful.

The route passes through two urban areas (Walnut Creek and Livermore). Rather than being annoyed by that interruption, I found it fun to have access to restaurants and grocery stores; the urban interludes provided diversity that I really enjoyed.

We have been hiking extensively in the Diablo Range for about 40 years, and I continue to love the landscape.

James’ Assessment

I really enjoy playing around with maps and working on possible new hiking trips. The East Bay has an extensive park system and trail network and we have spent much less time there than on the peninsula where we live and in Marin County. So we have recently been taking more day hikes in the East Bay and I have been working on new backpacking routes. This Vallejo to Milpitas walk is my latest effort. It worked out well as a route.

One thing that I realized on this trip is just how much upland Oak-Savannah habitat can be found in the northern Diablo Range. This is scenically one of the loveliest places to walk, with sensuous rolling hills covered with grasses and wildflowers and crowned with scattered stately Live, Valley, Blue and Black Oaks. It is just a treat to have such a beautiful and somewhat rare place to explore so close to home.

Notes for Potential Hikers

Route Description

Much of the information in the Big Diablo Loop Route Guide is still relevant today and can be used for guidance for this walk as well. There have been several additional pieces of public land with useful trails added since we walked the Big Diablo Loop and some of these have been included in the Vallejo to Milpitas walk.

There are numerous grocery stores and restaurants in Martinez, Walnut Creek and Livermore. It is easy to alter the route to patronize any of these options.

Our route is just that: our route. There are many places where alternatives can be taken to lengthen, shorten, or otherwise change the route. Hike your own hike. We did, however, spend a lot of time mapping the route through the urban areas to minimize the amount of walking along busy streets.