Enjoy a self-guided geological tour of Round Top. The run has 360-degree views of San Francisco, Mt. Diablo, and the Delta!
Check yourself for ticks after running in this park.
You can pick up a map at the Sibley Staging Area and follow the self-guided tour if you'd like.
From the Sibley Staging Area, take the Round Top Loop Trail
to the EBMUD Water Tank. You'll see dark basalt dike.
Continue on the rocky, fully exposed Round Top Loop Trail
to the Quarry Trail
. You'll see the iron-rich red rocks, readily oxidized by atmospheric exposure.
As you head to the Pond Trail
, the fire trail is exposed and has amazing views of the canyon. When you hit the road, turn right up the hill to Pond Trail
. The trail provides shade, but beware of the family of quail living in the bushes. They flew out and scared the crap out of me. The pond is filled with frogs. There is a picnic table at the pond, but the mosquitoes will drive you away from this spot.
Go back up Pond Trail
and take the first unmarked trail to the right. The trail turns into a narrow, overgrown singletrack trail. The map doesn't show the trail connecting to Volcanic Trail
, but it does connect at sign #11 with a view of Siesta Valley.
Continue to sign #10 to see the red rock formations. At sign #9, has remains of the old volcano. Signs #6, #7 and #8, there are red rocks and basaltic flows.
Continue on Volcanic Trail
and take the unmarked trail up to the ridge. You'll enjoy some of the best views of the Bay Area from the ridge. Stop and check out the labyrinths on your way to Quarry Pit (sign #2). The quarry contains the largest labyrinth in the park.
Take the singletrack Round Top Loop Trail
back to the parking lot. The trail is tree covered.
Park information: ebparks.org/parks/sibley