Mount Diablo State Park
Up to the Peak
Neil Wiley

It’s a long drive up Interstate 680 to Danville, and even after you reach the park, you drive 15 minutes before reaching the Southgate entrance. If you don’t stop for views, snacks, and potty breaks, it will take another half hour and 17 curvy miles to reach the summit. Yes, it’s a longer drive than up Mt. Hamilton or Umunhum, and Diablo is only the third-highest Bay Area mountain. So why do it?

You’ll see more. To the west is the San Francisco skyline and the entire Bay Area. On a clear day, you may see Yosemite to the east, or Lassen Peak 181 miles to the north.

And that is just the background. You can also look down on 20,000 acres of open country, with mountains, giant rocks, lovely meadows, and green valleys.

The drive up is relieved by taking time to enjoy a great variety of landscapes, including scenic-view spots, picnic areas, and rest stops. Why hurry? It’s not the destination; it’s the journey.

You may be tempted to drive up to the upper parking lot, but on busy days, the twenty-minute parking limit may be enforced. Better to park at the lower parking lot, and take a short walk up to the castle-like Summit Visitor’s Center built with local rocks. This gives you time to visit the museum, walk around the observation deck to see a 360-degree view, and shop for snacks, books, maps, and gifts.
On the way to the lower parking lot, you’ll see signposts on both sides of the road for the Mary Bowerman Loop. (Be sure to ask for an interpretive guide at the visitor’s center.) If you cross the road to the trailhead, you can follow the numbers in the guide. You can walk the trail in about an hour. It’s less than a mile around the mostly-flat loop, but you may make several stops to see the views.

The first part of the trail passes by several different oak species, and some leave-it-be poison oak. You pass greenstone on the cliff faces. This volcanic rock was deposited on an ancient sea floor about 100 million years ago. A little further, you can touch some graywacke, a sandstone sediment.

Still on the west slope, the dirt trail becomes a smooth concrete sidewalk. Soon, we are on an observation deck, complete with free telescopes. It’s a great place to view the San Francisco skyline.

Past the concrete deck, the trail is reduced to a dusty path. On the cliff above are red-brown chert and white quartz rock.
Our next view subject is Mt. Zion. The mountain is identified by highly visible terraces created by mining for diabase, a material used for roadbeds and house foundations. Operating since the 1940s, the mine is still in use.

As the path turns a corner to the east, North Peak dominates the landscape. To the left is the Joaquin River Delta. To the right are hills of ancient sediment.

The trail turns to the south, displaying a giant dark monolith called the Devil’s Pulpit. In the distance are wide grasslands. Sagebrush lizards skitter through the dust under chaparral, junipers, yerba santa, and chamise.

If you are afraid of an unprotected dropoff, you may not like this section of trail. It’s short, however, and you are soon at the road just above the lower parking area.

Back in your car, you can enjoy a picnic with views at the Juniper Campground, Look Out Point, or Livermore Valley Overlook. Further down the road to Southgate are quieter picnic areas called Maple Nook and Bridal Nook.

Looking for another relatively easy hike? Park your car at Curry Point, the trailhead for several trails, or drive down to Rock City to see Sentinel Rock, Elephant Rock, Fossil Ridge, and the Wind Caves. To see more of the park by car, you can take the road to Northgate.

Of course, there is more. Mount Diablo hosts 200 miles of trail. Just be sure to carry a map. You can get a giant fold-up map for $6 at the visitor’s center.

Finding the park is easy. To enter via Southgate, take Interstate 680 to exit 39 (Diablo Road). Follow Diablo Road through several turns to Mount Diablo Scenic Boulevard. Follow the arrows on small park signs, or if you have GPS, get directions to 2087 Mount Diablo Scenic Boulevard, Danville, California. The park is open from 8 a.m. to sunset. The Summit Visitor’s Center is open from 10 a.m. to 4 p.m. Entry fee is $10 per car. Seniors get a $1 discount.

Yes, it’s a long drive to the Mount Diablo summit, but it’s a unique experience. As the Dali Lama said, “Every year, go some place you have never been before.” Mount Diablo is one of those places.