Sibley Volcanic Regional Preserve

Sibley Volcanic Regional Preserve

Ten million years ago lava flowed through the hills that now make up Sibley Volcanic Regional Preserve. Today, it’s a great place to explore dog-friendly trails with views of the surrounding volcanic landscape.

Start at the Skyline Boulevard Staging Area and pick up a self-guided volcanic walking tour brochure. This hike features a heart-shaped labyrinth, several grassy vistas, and a once-extinct volcano. Read this first!

How to Get There

In the Berkeley Hills lies one of the most unusual regional parks in the East Bay: Sibley Volcanic Regional Preserve, home to an extinct volcano and a series of mysterious labyrinths. Millions of years of geological history lie here to uncover with a self-guided tour and open hills to explore on different crisscrossing trails.

Begin the loop hike at the Sibley Staging Area and park in the small lot, paying attention to the “Dogs Allowed Off-Leash” signs (the number of inconsiderate professional dog walkers here has reached absurd levels). Check out the interpretive panels and grab a brochure that lists 11 sites to visit on the tour.

A paved Quarry Trail heads north from the parking lot to join the end of the Volcanic Trail and connects with a short trail segment that descends to two ponds. The Volcanic Trail, once a quarry haul road, contains most of the stops on the tour. Continue on the trail until it curves to the right near Site No. 5. Here, look down at a delicate heart-shaped maze carved into the quarry floor, created by local East Bay psychic Helena Mazzariello.

Volcanic Trail

The hike here reveals not only the innards of an extinct volcano but also several hidden labyrinths. Begin at the Sibley Staging Area on Skyline Boulevard. Dogs are welcome on this trail as long as they respond to voice commands.

The paved Overlook Trail leads to the preserve’s visitor center, where you can pick up a map for the self-guided volcanic tour. The park’s main attraction is the Round Top Volcano, an eroded remnant of a basaltic volcano from the Miocene epoch that erupted some 10 million years ago.

Once you’re ready to begin the tour, head down Volcanic Trail past a quarry haul road. The path passes a couple of ponds and eventually intersects with the paved Round Top Loop Trail, which circles Round Top Peak. When the trail splits, take the middle path. After the trail crosses Quarry Trail, a post numbered 5 on the self-guided volcanic tour map reveals the Mazzariello Labyrinth. More places to also visit by clicking here.


A mysterious labyrinth has been found tucked into the hills at Sibley Volcanic Regional Preserve. A solitary maze carved into volcanic rock, it has been walked by people looking for peace and serenity. Many leave trinkets and personal offerings in the center of the maze. A labyrinth is a sacred and mystical place that brings together opposites such as life and death, light and dark, and male and female.

Directions: To find the Mazzariello Labyrinth, start at the Sibley parking lot and head uphill on the trail to the right (when facing the restrooms) for about a mile. Keep an eye out for a sign that says “Dogs Allowed Off Leash”; this is your clue that you’re on the right path.

Continue on this trail until you reach a crossroad with the Round Top Loop Trail. At this point, you should be able to see the Mazzariello Labyrinth clearly. It has a diameter of about 50 feet and is outlined with vegetation that has grown over the years.

Visitor Center

Sibley Volcanic Regional Preserve is a place where it’s possible to feel like you are a million miles away from the urban hustle and bustle. It’s also a place to discover the rocky body and layered underpinnings of one of the Bay Area’s most intriguing geological features—an extinct volcano.

Park at the paved staging area, then walk over to the visitor center for a map of the self-guided tour. From there, the paved Round Top Loop Trail circles the summit of the 1,763-foot Round Top. The lava-formed Volcanic Trail includes most of the stops on the tour, while Quarry Trail and Pond Trail are shorter detours.

Most trails are hiking and equestrian only, but there is a multi-use trail that connects the preserve to Skyline Trail. Dogs are allowed, on leash only. The Mazzariello Labyrinth (located on Volcanic Trail) is the preserve’s first man-made labyrinth, constructed by East Bay artist Helena Mazzariello in 1989. It is open to visitors for meditation and prayer. Next blog post.


Driving directions from Century Pyramid to Sibley Volcanic Regional Preserve

Driving directions from Sibley Volcanic Regional Preserve to Temescal Regional Recreation Area